Physiology and pharmacology of a traveling first aid kit

It is common knowledge that most tourists are completely ignorant of medicines. Hundreds of unpronounceable names, pages of indications, contraindications, dosages - is it really possible to learn all this? It’s not very realistic, but it’s not really necessary either. After all, in any decent first aid kit there is a list where all this is written. What do you need? You need to know, at least in general terms, how one group of drugs differs from others, what and how they act, what the tactics of their use should be. And the missing specific information can always be found in the annotation for the medicine, in the literature, on the Internet.

In this lecture we will try to wade through the thorns of pharmacology to understand the principles of drug use. Let's go!

Painkillers: what to choose?

There never was a philosopher who could patiently endure a toothache
U. Shakespeare

Analgin, baralgin, aspirin, paracetamol, efferalgan, nurofen, ketanov, voltaren, caffetin... - a doctor standing in front of a pharmacy counter is dizzy from the countless familiar and unfamiliar names. What do these drugs have in common and how do they differ from each other? To begin with, we note that it is necessary to distinguish between the name of the active medicinal substance and the name of the drug. Each manufacturing company strives to give its own new trade name to a drug containing a long-known medicinal substance. It is impossible to remember all trade names. But often a medicine with a scary label turns out to be a long-time acquaintance; it is worth reading the active substance on the package. Above, we have deliberately mixed trade names and substance names into a single mess to show the confusion that arises. We will not do this again, but will mainly use the names of the active ingredients, giving trade names in brackets.

Most of the drugs listed belong to a group called non-steroidal anti-inflammatory drugs (NSAIDs). All NSAIDs have a single mechanism of action - they inhibit the synthesis of prostaglandins. Prostaglandins are substances that are produced in different parts of the body and perform a surprising number of functions. Firstly, they play an important role at the site of inflammation. By regulating its manifestations such as pain, temperature, redness. The source of inflammation is a “cold” joint, a “aching” tooth - prostaglandins cause a lot of trouble, and NSAIDs allow you to fight back against them. With a cold, inflammation also occurs, and NSAIDs are effective in reducing fever. However, one must understand that these wonderful remedies, while eliminating the symptoms, do not have any effect on the cause of the disease. Other functions of prostaglandins are protecting the gastric mucosa from the acid present in its lumen, regulating blood clotting and bronchial tone. There are side effects associated with this, i.e. undesirable effects of NSAIDs: development of stomach ulcers, increased bleeding time, possible provocation of an asthmatic attack. There is a widespread legend that NSAIDs damage the gastric mucosa only because they come into contact with it when taken orally. There are even enteric forms of these medications that supposedly do not cause ulcers. But no matter how the NSAID enters the body, it will still reach the gastric mucosa through the blood and reduce the synthesis of beneficial prostaglandins in it - the result is clear. Also, prostaglandins increase uterine contractions, so NSAIDs can delay labor (which, I hope, is not relevant during a hike) and effectively reduce pain during menstruation (which, alas, can be relevant).

Now let’s look at the differences between the drugs. Despite the generally general mechanism of action, there are nuances. Different NSAIDs have different effects on prostaglandin synthesis in different parts of the body.

Acetylsalicylic acid (aspirin) is one of the most popular NSAIDs. However, it's not the best at all. Having a relatively weak analgesic and anti-inflammatory effect, aspirin has a pronounced effect on the gastric mucosa and can cause “aspirin asthma”. This substance has a unique feature - among all NSAIDs, it inhibits blood clotting to the greatest extent. We will not go into the mechanism of this phenomenon, we will only say that, paradoxically, small (125 mg/1 time per day) doses of aspirin have the greatest effect on coagulation. What is of practical importance, incl. and on a hike. For example, if we want to prevent blockage of blood vessels in a frostbitten limb by thrombi (blood clots), we should use aspirin and in smaller doses than for pain relief.

Analgin (active ingredient - metamizole-sodium) is even more popular and, remarkably, even more harmful than aspirin. Having a similar analgesic effect, it, among other things, can cause serious disturbances in the blood system (in its cellular component). Therefore, it is better to throw this remedy out of the medicine cabinet.

What should we replace it with? For example, on ibuprofen (nurofen) or on ketoprofen (ketonal). These drugs are similar in effectiveness to analgin and aspirin, but cause fewer side effects. Ketoprofen can be injected if it is not possible to take it orally (for example, with a migraine accompanied by vomiting) or if you want it to act faster.

Is there an ideal NSAID that would have no side effects? Trying to create such a remedy, pharmacologists developed the so-called. selective cyclooxygenase-2 inhibitors (celecoxib, rofecoxib (Viox), etc.), which quickly gained popularity. However, in 2005, rofecoxib was found to increase the risk of cardiovascular diseases such as myocardial infarction. Therefore, these drugs are treated with caution [7].

Of the stronger NSAIDs, the most common are diclofenac and ketorolac. In diclofenac (Voltaren) the anti-inflammatory effect is more pronounced than the analgesic effect. Therefore, it is well suited for inflamed joints, sprained ligaments, tendons - excessive inflammation leads to damage to these structures. Diclofenac has a relatively pronounced effect on the gastric mucosa, so it is best to apply it topically in the form of a gel or ointment. ketorolac, on the contrary, has a more pronounced analgesic effect. Ketorolac (ketanov) is one of the strongest non-narcotic painkillers. In the form of an injection solution, it is very useful in a travel first aid kit. Unfortunately, this remedy not only has a pronounced analgesic effect, but also a damaging effect on the gastric mucosa. Therefore, it is not recommended to inject ketorolac for longer than 5 days in a row.

Of the most popular remedies, we have not yet named paracetamol, or acetaminophen (Efferalgan, Panadol), and this is no coincidence. Paracetamol is not an NSAID: it inhibits prostaglandin synthesis only in the brain and has no anti-inflammatory effect. In terms of analgesic and antipyretic effects, paracetamol is similar to analgin and aspirin. In terms of side effects, it is safer than them and therefore quite acceptable for use. However, it should be remembered that the daily dose of paracetamol (4 grams) should in no case be exceeded, otherwise severe liver damage may occur. The fact is that this medicine is processed in the body into a toxic product; if there is little of it, the toxin is quickly neutralized and has no damaging effect. But, if you exceed the dose, and before it has time to neutralize, the poison will damage the liver.

So, we're done with NSAIDs and similar drugs. They are combined under the name “non-narcotic analgesics”. Although we now already know that NSAIDs are not just analgesics, but also anti-inflammatory, antipyretic and anticoagulants. Here I want to look at antispasmodics, because they are often sold in the form of mixtures with non-narcotic analgesics. Antispasmodics relax smooth muscles - fibers that contract the walls of the ureters, bile ducts, uterus, blood vessels and other organs. Therefore, they are used for renal and hepatic colic, painful menstruation, and have a slight effect on blood pressure (reduce it). The most commonly used are papaverine (its mixture with analgin - baralgin) and drotaverine (No-Shpa).

In addition to antispasmodics, non-narcotic analgesics are often mixed with other medications - caffeine, vitamin C, antitussives, substances that reduce nasal congestion, etc. As a result, many mixtures such as Coldrex, Fervex, Caffetin, Panadol extra.. appear on the shelves. The last two drugs contain paracetamol and codeine - a weak narcotic analgesic that enhances the effect of paracetamol and has an antitussive effect. And yet they are sold without a prescription: the ratio paracetamol:codeine is so high that a potential drug addict’s liver will die much earlier than euphoria occurs.

In severe cases, non-narcotic analgesics are not enough. For example, a hip fracture cannot be anesthetized even with ketorolac. Despite the fact that in the case of serious injury, the presence of drugs may be critical for the prognosis, we will not consider them in detail, because they are not available to us. The main group of narcotic analgesics are the opioids. These include morphine, promedol, butorphanol (stadol), etc. Such a well-known drug as tramadol is an opioid, but has a relatively weak analgesic effect, comparable to that of ketorol. If you do have opioids in your medicine cabinet, keep in mind that they depress breathing (to a lesser extent this applies to tramadol)! Therefore, they are contraindicated if there is already depression of consciousness, for example, with a traumatic brain injury. Another potentially dangerous effect of opioids is peripheral vasodilation, which in a situation of shock can lead to deepening of the shock.

But in case of serious injuries, it is best to use local anesthesia. The advantages are obvious: pain is effectively relieved, and side effects are minimal. The disadvantages are also obvious - you need to be able to use local painkillers, know where and how to inject them. The most common are novocaine and lidocaine, but bupivacaine is more suitable for us - an effective and long-lasting remedy. Remember that there are allergies to local painkillers - it’s worth asking all participants before the hike whether they have an undesirable reaction to novocaine (if the participant had his teeth treated by a dentist and there were no problems, it most likely does not exist).

It is not for nothing that we put the topic of pain relief in first place. The point is not only that in any campaign, analgesics are one of the most popular groups of drugs. Adequately controlling pain is one of the few ways to really help a fairly severe victim.

Heart, blood vessels and our modest capabilities.

Some drugs are more dangerous than the diseases themselves
Seneca

The cardiovascular system is, as you might guess, the heart and blood vessels. Let us briefly recall something that perhaps not everyone remembers from school. Blood in the human body is a universal system for transporting substances. The most important thing for us is that the blood from the lungs carries much-needed oxygen to all other organs. The vessels act as a “pipeline” for blood, and the heart acts as a “pump” that sets it in motion. Vessels called arteries come from the heart; as they approach the organs, they branch more and more, turning into smaller and smaller vessels and, finally, ending in the organs with the thinnest “tubes” - capillaries. Blood from the capillaries collects in vessels leading to the heart - veins. Now we have to complicate the picture. The fact is that in the cardiovascular system there are two circles, large and small. First, the heart sends blood to a small circle: it goes through the arteries to the lungs, where it is saturated with oxygen, and returns through the veins to the heart. Then this blood enters a large circle: through the arteries it goes to the organs that take oxygen, through the veins it goes back to the heart. And then the blood is sent back to the small circle. Actually, there is no beginning and end here.

How can we monitor the functioning of the cardiovascular system? Of the many parameters that characterize it during a hike, at best two can be measured: pulse and blood pressure. With the pulse, everything is more and more clear: without going into details, we can say that when we feel the pulse, we feel how the heart contracts. Pressure is a little more difficult. What does it depend on? Let us immediately note that the analogy between the cardiovascular system and the water supply is far from complete: vessels are not just “pipes”; their walls can contract and expand. As a result, blood pressure changes. In addition, the pressure depends on the amount of blood (by the way, it is normally about 5 liters) and on how effectively the heart contracts.

How can you influence the functioning of the cardiovascular system? You can reduce or increase blood volume, dilate or constrict blood vessels, stimulate heart contractions. This, of course, does not exhaust the possibilities, but, as a rule, nothing else is used during a hike. Situations in which you want to increase blood volume (this condition is called hypovolemia) are, first of all, bleeding. How to increase it? The answer is simple - pour liquid into the vascular bed. But, unfortunately, in practice this is no longer so easy to do. Firstly, it is obvious that you cannot pour water from a puddle or even from a mountain river into your blood; this requires special solutions. And you will have to carry these solutions on your back! Secondly, in order to infuse them, you need to be able to inject drugs into a vein. Still, it’s worth thinking about including blood substitutes in your travel first aid kit, because... they are indispensable in acute situations. In terms of effect/weight ratio, the so-called colloids - solutions that are capable of “luring” fluid from surrounding tissues into the vessels. There are many colloids, but most of them are sold in glass, which is very inconvenient. In a wonderful lightweight plastic package you can find, for example, one of the most modern colloids Voluven.

diuretics have the opposite effect. These drugs stimulate the kidneys to excrete fluid, causing the amount of blood to decrease. The most common drug in a travel first aid kit is furosemide (Lasix) - one of the most powerful diuretics. Why are these funds needed? When the heart cannot cope with its work, it is useful to reduce this work. And the less blood, the easier it is to pump. Therefore, diuretics are widely used in the case of so-called heart failure. But on a hike such situations arise quite rarely. Another idea is to use diuretics for swelling. The logic is simple: edema means a lot of water, which means that when there is edema, you need to remove the water. However, alas, direct and clear logic does not always lead to the right conclusions. Because it’s not that simple, there are different types of swelling. If the swelling is caused by heart failure, diuretics will be effective. If not, it's not necessary. We are primarily interested in high-altitude pulmonary and cerebral edema. Unfortunately, there is no evidence-based evidence for the treatment of these conditions. Therefore, we have to base all recommendations on analogies and physiological considerations. It should be understood that diuretics, by reducing the amount of blood, impair the delivery of oxygen to the tissues. And the cause of high-altitude edema is precisely the lack of oxygen. Therefore, the rationale for using furosemide for high-altitude edema is disputed. This is currently not recommended [2]. There are also other ideas regarding the use of diuretics while hiking, in particular, proposals to use them in case of head injury to prevent cerebral edema. But furosemide and similar drugs have a subtle effect on the water content in the brain, and, ultimately, their effectiveness in reducing its amount is, at least, small [13]. We suggest, guided primarily by the principle of “do no harm,” not to use potent drugs without being sure that this is necessary. And, moreover, without being able to correct their potential side effects. It is up to you to choose whether or not to take furosemide into your first aid kit, but if you do take it, use it with great caution. A decrease in blood volume is “bad” in most cases, but in the case of bleeding (which accompanies almost any injury) it is simply absolutely unacceptable!

Diuretics also include acetazolamide (diacarb). But we are not interested in its diuretic effect, which is quite insignificant. This remedy appears to be one of the few truly effective for the prevention and treatment of acute mountain sickness. We talked about this in detail or will talk about it at the lecture on high-altitude medicine, but now we will make only a small digression concerning the medicinal aspect of adaptation to altitude. There are many means that are proposed to be used to facilitate the acclimatization process [14]. For each of them there is an explanation why this wonderful substance helps the body adapt to altitude. But only for 2-3 of them, these are acetazolamide, dexamethasone (we’ll talk about it later) and, according to some data, Ginkgo extract (such a relict plant), there are competent studies on people confirming their effectiveness [5]; One study showed the effectiveness of vitamins [1]. Which, however, does not mean that all other means are not effective; maybe people just haven’t gotten around to them yet. What should a poor field medic do? There are two approaches here, creative and skeptical. Some enthusiastically fill their medicine cabinet with adaptogens (O. Yanchevsky), some call all these remedies “medieval obscurantism” (A. Dolinin). Choose for yourself which approach you prefer.

So, we talked about how you can influence blood volume. The second way to interfere with the functioning of the cardiovascular system is to medicamentally change the tone of blood vessels, i.e., in more human terms, their expansion or narrowing. There are a lot of drugs that affect vascular tone and we have no opportunity (and, indeed, no desire) to systematically describe them. Therefore, we will only talk about individual drugs. Let's start with vasodilators. Any first aid kit will probably contain nitroglycerin. This substance is able to quickly and effectively dilate blood vessels, and therefore is used for angina. What is angina? When the vessels supplying the heart become narrowed or blocked, it begins to lack oxygen. While the load on it is minimal (for example, a person is sleeping), the heart does not need a lot of oxygen. But, as soon as the need for oxygen increases (the person runs), the heart muscle begins to acutely feel its lack. Which is manifested by a characteristic compressive pain behind the sternum. Such episodes, naturally, are not characteristic of a healthy heart and mainly occur in older people. Therefore, angina pectoris is not very likely while hiking, although it is possible. Fortunately, most often pain in the heart area occurs for other reasons. And yet we must not forget about angina. Because if timely assistance is not provided in this condition, myocardial infarction may develop. The bottom line is that cells cannot live for long without oxygen and, if its supply is not restored, they die. How to restore oxygen supply to the heart?

You probably already guessed where the thread of reasoning leads: here we just need nitroglycerin, which dilates blood vessels! When the vessels in the body are dilated, it is easier for the heart to pump blood through such wide “pipes”; in addition, by dilating the vessels that feed the heart itself, nitroglycerin ensures better oxygen delivery. It is important to use this medicine correctly: firstly, the tablet or capsule should be placed under the tongue, and secondly, it should be taken sitting. Because nitroglycerin, dilating peripheral vessels, causes blood to flow out of the brain; in a standing position, when gravity works most against the blood supply to the brain, this effect is especially pronounced. As a result, taking nitroglycerin while standing can cause you to fall! It is less effective when lying down. Nitroglycerin is rapidly absorbed and acts quickly. If the effect does not occur a few minutes after taking the tablet, it means that it will not occur - in this case, you need to take another tablet. If, despite repeated use of nitroglycerin, the pain does not go away, there are two options: either it was not angina, but pain of a different nature, or, despite all our efforts, the lack of oxygen could not be eliminated. The second condition is called acute coronary syndrome (a special case is myocardial infarction; it is impossible to clarify the diagnosis during a hike). In this case, the pain is very severe and must be stopped. Unfortunately, non-narcotic analgesics are not very effective here; the best remedy is morphine. In addition, aspirin (160-325 mg) should be given, this is due to its anticoagulant effect, its use reduces mortality by 25%! Nitroglycerin should be continued (0.4 mg every 5 minutes). But, most importantly, the victim needs to be lowered, and the sooner the better! Firstly, you need qualified medical care, and secondly, you need oxygen, which, as you know, is scarce at altitude.

A few words about valocordin. Theoretically, it, like nitroglycerin (only through a different mechanism), can dilate the blood vessels of the heart. In fact, this drug has a very weak, almost zero effect. Nevertheless, having a pronounced pleasant taste, it can be useful in the medicine cabinet as a psychotherapeutic agent.

Any organ, not just the heart, can suffer from a lack of blood supply. In the cold, due to lack of blood supply, the arms, legs, tip of the nose, earlobes - the parts of the body most distant from the center of the body - begin to freeze. The mechanism of frostbite occurrence is as follows: the body’s first reaction to entering a cold environment (for example, when leaving a tent) is the dilation of blood vessels in the places most vulnerable to frost. As a result, at first the hands are without gloves and the face turns red: blood rushes to them. Since the blood is hot, it warms these parts of the body and prevents them from freezing. But after some time, the second phase of the reaction to cold may occur - a narrowing of previously dilated blood vessels. The fact is that limbs, earlobes, tips of the nose, cheeks are not the most important organs. And if, in order to keep them warm, you have to sacrifice the temperature of the blood flowing to the heart, brain and other vital organs, such a compromise is unacceptable. Therefore, in conditions of poor adaptation to cold, one has to sacrifice the least valuable and constrict the blood vessels in the extremities - this is how frostbite occurs. It is not surprising that for their prevention it is often proposed to use vasodilators, the most popular of which are ethyl alcohol and trental. Indeed, they dilate, among other things, the vessels in the extremities and can prevent frostbite. But this approach is very dangerous, and you can probably already guess why. A classic example is a drunkard freezing in a snowdrift. After drinking alcohol in the cold, at first he feels a pleasant warmth throughout his body, but soon this feeling passes and is replaced by drowsiness - the person begins to freeze: the heat was wasted on warming the limbs, and in the end it was not enough to maintain life. Likewise, when hiking, using vasodilators in the cold can lead to general cooling. It's a different matter in a warm tent. To warm up a victim brought to a warm room, you can use trental. Alcohol is worse because it has many known side effects.

Agents that dilate blood vessels and/or reduce pressure in other ways are used for arterial hypertension, i.e. in case of increased blood pressure. There are a lot of them and choosing such a medicine is a very difficult task. Therefore, we will not even dwell on these remedies: if someone in the group suffers from such an illness, before going on a trip he should consult with his doctor and follow his instructions in terms of drug therapy. While we are talking about blood pressure lowering agents, we note that one of them, nifedipine, should be in your travel first aid kit for a specific reason: it is used for high-altitude pulmonary edema (dilates blood vessels in the lungs) [2].

In many lists of camping first aid kits, almost the first place is given to such drugs as caffeine, niketamide (cordiamin), sulphocamphocaine. These drugs are called analeptics and stimulate the cardiovascular and respiratory systems. Moreover, the main mechanism of their action is the activation of the brain center responsible for these vital functions. You can find recommendations for the use of these drugs for almost all acute conditions. They motivate it something like this: if the body feels bad, it means something is not working well in it, which means it needs to be “spurred on.” But, as a rule, the body itself takes care of “stimulating” what is needed, when it is needed and in the right way, and our intervention here is completely unnecessary. All we achieve by prescribing analeptics is to increase oxygen consumption in the brain, but in acute situations there is usually not enough oxygen anyway! Perhaps the only case when these remedies can be useful is to warm up a frozen person: the cold inhibits the work of the centers in the brain and, as a result, vital functions are disrupted. Although subcutaneous administration of, for example, cordiamine to a person extracted from an avalanche or from a mountain river will not give any effect at all. After all, under the skin in this case, the blood flow is practically zero (small vessels are narrowed from the cold) and the drug is unlikely to go much further than the skin. In general, you can, of course, take these products with you in the first aid kit, but you don’t have to take them, and this will change little for the worse.

So, there are many means to influence the functioning of the cardiovascular system, and there is great scope for their use during a hike. However, when deciding whether to give a patient another medicine, one should be guided primarily by the principle “Do no harm!”

Antimicrobial agents: “life against life”

Perasperadastra

Antibiotics are special medicines. Their action is directed not at the systems of the human body (macroorganism), but at microorganisms that can settle in the macroorganism. Why do we say “antibiotics”, but write “antimicrobial agents” in the title? Do these concepts mean the same thing? Are sulfonamides, for example, antibiotics? There is a terminological subtlety here. Antimicrobials are all substances that kill or slow down the proliferation of microorganisms (microorganisms include bacteria, protozoa, fungi and viruses). There are antimicrobial agents of non-selective action - antiseptics, we will not talk about them - and selective action. Antibiotics are traditionally called only those selective antimicrobial agents that are (or were previously) obtained naturally (for example, from mold). Therefore, for example, streptocide, which is essentially no different from antibiotics, is not called an antibiotic, because synthesized artificially. Also, the popular drug ciprofloxacin (Tsifran, Ciprolet) is also not formally an antibiotic. Of course, bacteria don’t know this, and they don’t care at all what pharmacologists call the substance that kills them. But we say all this so that the listener understands that all the same rules that apply to antibiotics apply to the use of the same sulfonamides.

What are these special rules?

Now let's move on from general principles to specific drugs. The first antibiotics were benzylpenicillins, which revolutionized medicine. However, being effective half a century ago, they have now lost their effectiveness for reasons that are already clear to you. Penicillins can cause allergies, so if you are going to use them, be sure to ask the patient if he has had any allergic reactions to antibiotics. But in general, these drugs are quite harmless, and this is their advantage. As for effectiveness, there are synthetic analogues of benzylpenicillins, such as ampicillin and amoxicillin, and they are more effective. Ampicillin is less absorbed in the intestine and can be used for intestinal infections (we will talk about intestinal infections later). Amoxicillin is especially effective when combined with substances that prevent bacteria from breaking it down. Such drugs - amoxiclav, augmentin, despite the substantial price, are quite worthy candidates for a traveling first aid kit.

Similar in mechanism of action to penicillins cephalosporins. These antibiotics are easily recognized by their names: cefazolin, cefaclor, ceftriaxone, cefixime. Currently, 4 generations of cephalosporins have been synthesized. With the exception of first generation drugs (cefazolin), cephalosporins have a good spectrum of action. Unfortunately, most of them can only be used as injections (parenterally). The exceptions are cefaclor and cefixime. Of the parenteral cephalosporins, the most convenient for us is ceftriaxone, because It is used once a day and can be injected intramuscularly. Just keep in mind that it is sold in powder form (since it quickly decomposes in the form of a solution) - keep a 1% lidocaine solution for dilution (lidocaine is used, not just saline, since administration is painful). And also, keep in mind that penicillins and cephalosporins are similar not only in their mechanism of action, and if the patient is allergic to penicillins, then there is a high probability of a reaction to cephalosporins.

You can often see ampoules of gentamicin in travel first aid kits. This antibiotic belongs to the aminoglycosides. Gentamicin is convenient because it does not need to be diluted and can be administered intramuscularly. And its price is very modest. In addition, it has been shown that if the daily dose of aminoglycosides is administered not fractionally - several times a day in parts, but once a day all at once, then this will only increase the effectiveness, and there will be fewer side effects. Therefore, gentamicin is very convenient to use. However, aminoglycosides have relatively serious side effects: they are toxic to the kidneys and can cause irreversible damage to the organs of hearing and balance. And their spectrum of action is more suitable for use in hospitals (the flora there is special). Whether or not to take them into your first aid kit is up to you. But, if you decide to take it, know that gentamicin is by no means the most modern option; there are aminoglycosides that are more effective, for example, amikacin.

We already mentioned doxycycline. It is cheap and effective, used orally (inside), but causes severe disruption of normal microflora (must be combined with antifungal agents), and is toxic to the liver. Together with tetracycline, doxycycline belongs to the tetracyclines. You've probably heard of tetracycline eye ointment. An antibiotic eye ointment is worth having in your first aid kit, especially if there are people in the group who wear contact lenses, and tetracycline is quite suitable for this role.

Even more toxic than tetracyclines Levomycetin (chloramphenicol).Levomycetin is an effective antibiotic, but its use is limited, because it can have a very pronounced effect on the blood system, causing, among other things, anemia, which is especially unpleasant at altitude. There is only one place for it in your travel first aid kit - topical ointment!

Another group of antibiotics of interest to us is the macrolides, which are widely used for respiratory tract infections. The most famous macrolide is erythromycin, but we are most interested not in it, but in azithromycin (sumamed). Sumamed is prescribed orally once a day for three days, which is where its convenience lies. But it is quite expensive.

Finally, finishing with antibiotics, before moving on to synthetic antibacterial agents, I would like to talk about the “best of the best” - carbapenems. This group of antibiotics acts on almost all microorganisms with rare exceptions. But it is precisely for this reason that they try to use them as rarely as possible: they are saved for those cases when nothing else helps. The most common are imipenem (tienam) and meropenem (meronem). The latter is more effective, but it can only be administered intravenously. Tienam can also be administered intramuscularly. It would probably be nice to have carbapenems in reserve as a last resort - and only as a last resort! - case (for example, diffuse peritonitis when quick evacuation is impossible). But it is clear that light weight and volume will not get by, and neither will the price. Therefore, this is more of an option for a first aid kit, which is one for several groups and lies in the base camp.

Now let's move on to synthetic products. First of all, sulfonamides should be noted. These include such widely known drugs as streptocide, sulfacyl sodium (albucid), phthalylsulfathiazole (phthalazol), sulfaguanidine (sulgin). And again, I would like to emphasize that sulfonamides are essentially no different from antibiotics, and it is unacceptable to swallow streptocide on a par with cough lozenges for colds, and phthalazol and sulgin - on a par with charcoal for diarrhea. Sulfonamides, like benzylpenicillins, having been invented a long time ago, have now lost their former effectiveness. But they did not lose side effects - dysfunction of the kidneys, liver and blood system, as well as high allergenicity. Therefore, the niche for them in the travel first aid kit is very narrow - this is local use in the form of eye drops (albucid) and in the form of agents that are not absorbed in the intestines (phthalazole and sulgin, we will come to this issue later we'll be back).

The effectiveness of sulfonamides increases significantly if you combine them with other substances. This is the drug co-trimoxazole, known as biseptol. Its tablet form, broad spectrum of action and price make it a possible candidate for a travel first aid kit, but the side effects do not make it attractive. It should again be understood that, although biseptol is not an antibiotic, before you start taking it, you should think no less than before drinking, for example, sumamed.

Another interesting antimicrobial agent is metronidazole. It is interesting because, unlike the above remedies, it acts not only on bacteria, but also on protozoa. So, if you drink water with Giardia in Asia, metronidazole will be indispensable to correct the consequences of this mistake. Metronidazole can be taken in tablet form. But keep in mind: its use cannot be combined with alcohol consumption! Metronidazole inhibits the enzyme that inactivates acetaldehyde, a substance that causes a hangover. Consequences - even death!

And finally, we are approaching one of the most popular travel antibiotics - ciprofloxacin (Cifran, Ciprolet, etc.). It belongs to the fluoroquinolones - a relatively safe and effective group of drugs. Unfortunately, ciprofloxacin is used so widely that it has noticeably lost its effectiveness. The fact is that in our country many low-quality drugs are used, which are “not reported” ciprofloxacin. And you already know the consequences of using low doses of antibiotics. The more alarming is the love of tourists for this drug. In this case, the “good old” principle does not apply. In addition, for respiratory diseases (i.e. diseases of the respiratory system), which are so common on a hike, ciprofloxacin is often not very effective. This antibiotic has similar, but newer and more effective, although less known, and as a result, less “spoiled” “relatives”, for example, levofloxacin (Tavanic), moxifloxacin (Avelox). They, unlike ciprofloxacin, are effective for diseases of the respiratory system, including pneumonia. But, like most new drugs, they are expensive. The advantage of ciprofloxacin is that it is the drug of choice for intestinal infections (we will talk about them when we discuss medications that affect the digestive system). Fluoroquinolones can be used both enterally and intravenously. In experiments on rat pups, it was shown that fluoroquinolones disrupt the formation of cartilage tissue. Therefore, in children they are used only for health reasons, i.e. when nothing else helps, and there is nothing left to lose. Although in rare cases when fluoroquinolones were used in children, no effect on cartilage tissue was observed.

Well, we have looked at the main groups of antibacterial antibiotics for us. A few words about antifungal agents. Most likely, they will not be needed on the hike, and they should only be taken if one of the participants has fungal diseases. The widely known nystatin is not absorbed from the gastrointestinal tract. As for antiviral drugs, the campaign uses only acyclovir (Zovirax) topically for herpes.

All. We're done with antimicrobials. Of course, there are many more of them than we have considered, but if you know at least this, it will be great. Don't be discouraged by the large amount of information. In reality, a traveling first aid kit usually contains 1-2 antibiotics, the choice of which depends on the personal preferences of the physician. It is highly desirable to have antibiotics in both oral and parenteral forms. Moreover, it is convenient to have the same remedy in different forms, then you can switch from one to another as the situation changes. Antibiotic ointments for topical use are also indispensable.

And in conclusion. Despite all the restrictions on the use of antibiotics and their undesirable effects, it should be understood that during a hike the situation is often very acute. And at high altitudes, in the heart of the mountains, from where evacuation is practically impossible, even a common cold can be an indication for the prescription of antibiotics.

Drugs affecting the digestive system

In case of major troubles, I deny myself everything except food and drink.
Oscar Wilde

Let’s make a reservation right away that we will not consider those medications that are required for the treatment of chronic diseases. Participants who have them must be dealt with individually. But in a basic first aid kit it is impossible to provide for everything, because the number of diseases is infinite, and the volume of the first aid kit is limited. Everything is impossible, but something is possible and necessary. Firstly, you should definitely expect diarrhea of ​​various etiologies, especially if you are traveling to Asia. Secondly, at altitude food is very poorly digested, and when descending down into civilization, it is digested even worse, because... it becomes several times larger.

Medicines used for diarrhea are known to everyone: these are adsorbents (activated carbon, polyphepan, smecta...), loperamide (imodium) - a symptomatic remedy. We want to dwell in more detail on the issue of antibiotic therapy. First of all, I would like to emphasize that antibiotics are a means of treating infection and, if diarrhea is not caused by a microorganism, they are of no use. How to distinguish an infection from ordinary poisoning - read, for example, Dolinina. When treating an intestinal infection, it is logical to use antibiotics that are not absorbed in the digestive system - these are phthalylsulfathiazole (phthalazole), sulfaguanidine (sulgin). If you remember, they belong to sulfonamides. But, as we have already said, sulfonamides are not very effective at present. And in modern conditions, the drug of choice for food poisoning is ciprofloxacin. ampicillin can also be used for this purpose. What to choose is up to you, but keep in mind that diarrhea is not so harmless: the dehydration it provokes under conditions of great physical activity and acclimatization to altitude sharply weakens the body.

Another important point in the treatment of foodborne infections concerns the use of loperamide. It is necessary to understand that this remedy is purely symptomatic, and it does not have any therapeutic effect. Moreover, by preventing the elimination of toxins, it can promote their absorption into the blood and, as a result, deterioration of the body’s condition. Therefore, loperamide should be used with great caution.

The gastrointestinal tract has two main ways of digesting food. Firstly, the stomach “kneads” it, and secondly, enzymes and proteins act on food, capable of breaking down molecules into smaller pieces. Therefore, to improve digestion, either the so-called. gastrokinetics, i.e. substances that enhance contractions of the gastrointestinal tract, or mixtures of enzymes. The first includes the well-known medicine domperidone (Motilium), the second - festal and mezim.

Another problem that a doctor will probably have to deal with on a mountain hike is heartburn. Its cause is increased acidity in the stomach. How to deal with acid? That's right, with the help of foundations! Of course, you shouldn’t swallow an alkali like “toilet duckling,” but weakly basic substances will be very useful. These are antacids. Their most famous representatives - "Almagel", "Maalox", being liquid, weigh quite a bit. But antacids are also available in tablet form - just ask at the pharmacy, you will probably find something. And for the tablets to work as well as the gel, you just need to chew them well.

And another group of drugs that are sometimes irreplaceable are antiemetics. The popular metoclopramide (cerucal) is quite suitable for this purpose. By the way, guess why it is useful to have it in the form of ampoules?

Glucocorticoids: panacea or bane?

Doctors are those who prescribe drugs they know little about, to treat diseases they know even less about, in people about whom they know nothing at all.
Voltaire

Now we have to look at a very interesting and extremely controversial group of drugs - glucocorticoids. In popular literature for tourists you can find, for example, the following description of these drugs:

"It has a strong anti-inflammatory, anti-allergic, anti-shock and anti-toxic effect, increases blood pressure. Indications: stressful situations, shock, poisoning, burns, injuries, asphyxia, etc. Used for allergic diseases, bronchial asthma, joint diseases, infectious diseases, hypotension, etc."

Aren't they wonderful tools? The flirtatious “etc.” is especially attractive. It would seem that in any difficult situation one can use glucocorticoids without hesitation. Is this true? Let's figure it out.

Let's start, as always, with physiology. What are glucocorticoids? Our body is regulated by many chemicals called hormones. Glucocorticoid drugs are analogues of the natural glucocorticoid hormones secreted by the adrenal glands (small glands located, as you might guess, above the kidneys). Glucocorticoids are called "stress hormones" because... they stand out in situations where the state of the body leaves much to be desired. Their effects are numerous:

In medicine, not only substances identical in chemical structure to natural glucocorticoids are used, but also their synthetic derivatives. Therefore, there are a lot of drugs in this group. The most common are prednisolone, methylprednisolone and dexamethasone. They differ from each other in activity, i.e. according to the dose required to achieve the same effect. The choice of a specific drug is rather a matter of taste. And the dosage can always be easily recalculated using the following rule:

(dose dexamethasone) = (dose prednisolone)/10 = (dose methylprednisolone)/8

Thus, dexamethasone is ten times more active than prednisolone and eight times more active than methylprednisolone.

Now let's move on to the most interesting part - the question of when to use glucocorticoids on a hike.

So, glucocorticoids are, of course, not a panacea, but they are not poison either. This is an interesting and, at the same time, extremely controversial group of drugs, and its place in medicine, apparently, will be clarified for a long time.

Drugs affecting the respiratory system

The doctor treats diseases, but nature heals
Hippocrates

We have already talked about medications that are used for severe inflammatory diseases of the respiratory system, such as pneumonia (pneumonia). These are antibiotics. Is it necessary to treat a common cold? Most often it is caused by viruses, and it is very difficult to kill them, and the harm from antiviral drugs is usually greater than from the cold itself. The body copes with colds on its own. But some medications can still be helpful. Why are they needed? Firstly, they alleviate the patient’s condition, and secondly, they help prevent the “descent” of inflammation into the lungs.

What kind of means are these?

Thus, there are many remedies for colds, and their correct use helps the body cope with the disease. But still, those who say that “a cold goes away in a week without treatment, and in seven days with treatment” are right in many respects.

In conclusion

I know I don't know anything
Socrates

We have tried to bring to you the most modern ideas about the pharmacology of the drugs included in the travel first aid kit. Naturally, a lot remained beyond the horizon, but still much more was told than “non-medics” were “supposed” to know. Having loaded into memory a huge amount of information about various medications that may be needed on a hike, it’s time to think: do I need this knowledge? Is it necessary to take and, even more so, use such a bunch of tablets, “shots” and other food? Yes, sometimes (to be honest, quite rarely) their presence in the first aid kit can be critical for the health of the participant. But, on the other hand, sometimes (to be frank, quite often) an incorrectly used medicine can turn into poison. Thirdly, practice shows that people who want to go on high-category mountain hikes in hard-to-reach areas and at the same time stay alive actively study medicine and include a fair amount of potent drugs in their first aid kits. Be that as it may, understanding the possible negative consequences of our work, we still decided to tell you all this. What to do or not do with this knowledge is your business.

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original article published here (Moscow State University tourist club website)