Antipyretic
It is called antipyretic, antipyretic, fever reducer, pill, syrup and febrifuge to any drug that reduces fever. They are usually medications that treat fever symptomatically, without acting on its cause. The most common examples are acetylsalicylic acid, ibuprofen, paracetamol, and metamizole.
Etymology
The term antipyretic comes from the Greek language, combining the prefix αντι-, which means "against", with the lexeme πυρ, πυρος, which means "fire" or "fever". Likewise, antithermal combines the same prefix with the stem θερμός, "heat".
Uses
Physical measures are the first non-invasive measure to combat fever, such as warm cloths (cold cloths cause a rebound effect) in the area of the head, armpits and abdomen or warm water baths, are a measure antipyretic in which no drugs are used. Associated with paracetamol, they lower fever more efficiently. Physical measures in isolation are only effective for a few minutes.
Administering antipyretics is a common practice in most people with fever, especially children. It is known that fever is a defense mechanism of the body, especially to activate the immune system to work more effectively. A rise in body temperature of up to 38°C is called a low-grade fever, and it is not a dangerous fever that needs to be brought down with medication. The underlying disease must be addressed, but due to the habits acquired by the population and by the medical community, antipyretics are prescribed and administered more because of parental anxiety and not because they really should be indicated.
The decision of which antipyretic should be used is based on its mechanism of action, pharmacodynamics, effectiveness, and side effects. Since most of the time the objective is to decrease the patient's temperature and discomfort and, if possible, not to alter the inflammatory response, unless it is exaggerated, paracetamol is recommended.
Most antipyretics are analgesics and may also be anti-inflammatory. Non-steroidal anti-inflammatory drugs, such as ibuprofen, are used in cases of inflammation and hemorrhoids.
Types of antipyretics
The best-known antipyretic medications are: acetylsalicylic acid (ASA) (also known by a trade name: aspirin), paracetamol (also acetaminophen), ibuprofen, and metamizole (also dipyrone).
Salicylates have antipyretic effects and are absorbed in the intestine, although mostly in the first part of the small intestine by passive diffusion.
An oral dose of salicylates presents the aforementioned effects in the course of half an hour, presenting its maximum effect between 1-3 hours and extending its effect up to 6 hours. In any case, care must be taken, since an abuse of salicylates can cause poisoning that leads to an increase in temperature, although it seems a contradiction. This reaction is due to increased oxygen consumption and metabolic rate due to uncoupling of oxidative phosphorylation.
Non-steroidal anti-inflammatory drugs (NSAIDs for short) are made up of unrelated organic acids, and they also have analgesic and antipyretic properties. NSAIDs work by inhibiting the enzyme cyclooxygenase so that they inhibit the direct biosynthesis of prostaglandins and thromboxanes. Most of the prostaglandins are pyrotogenic, that is, they cause fever.
Aspirin is the only one that binds irreversibly to cyclooxygenase; its mechanism shows a rapid deacetylation producing salicylate, which is the one that really has antipyretic properties.
As already mentioned, NSAIDs have antipyretic effects in that they lower elevated body temperature. This drop in temperature is caused by vasodilation of blood vessels and may be accompanied by sweating.
NSAIDs are capable of displacing both proteins and drugs from the active site.