4 Medications to Lower Fever
Fever is a common symptom that occurs during infections, although it may not appear in immunocompromised patients. In this article, we’ll be talking about 4 different medications to lower fever and comparing their effectiveness.
Medications to lower fever belong, for the most part, to the group of non-steroidal anti-inflammatory drugs, although each one has its own peculiarities.
If you want to know a little more about these drugs, we’ve prepared the following article to answer all your questions. Keep reading!
How does a fever occur?
Fever is the body’s response to the presence of substances known as pyrogens. These can be produced by your own cells, or also by foreign microorganisms. In the first case, they’re called endogenous pyrogens and, in the second, exogenous pyrogens.
When faced with an infection under normal conditions, the immune system is activated, especially its cellular component, which includes leukocytes. These release substances in order to eliminate microorganisms, such as pro-inflammatory cytokines, interferon, and tumor necrosis factor. These, in addition, act as endogenous pyrogens.
For their part, bacteria have some molecules on their surface and release other substances that act as exogenous pyrogens, in addition to allowing them to survive in various environments. This group includes peptidoglycans and lipopolysaccharides.
Regardless of the origin of the pyrogens, they travel through the bloodstream to a portion of the hypothalamus, where nerve signals are activated which are capable of producing the characteristic symptoms of fever: chills, high temperature, general malaise, and tachycardia, among others.
Medications to lower fever
Next, we’re going to describe the characteristics of paracetamol, acetylsalicylic acid, ibuprofen, and metamizole. They all share some mechanisms of action, especially regarding the inhibition of the cyclooxygenase pathway. This, as you’ll see later, produces inflammatory mediators capable of producing fever.
This is one of the best-selling drugs worldwide due to its few adverse effects and that a prescription isn’t necessary to acquire it.
In fact, according to a publication of the Business Federation of Spanish Pharmacists, during 2018 12.8 million units were sold throughout the country, making it the fourth drug on the list.
In addition to its antipyretic effect, it’s also effective as an analgesic, which is why it’s able to reduce pain in many common conditions such as tension headache. In addition, it’s one of the few medications that pregnant women can safely consume.
Mechanism of action as a fever-reducing medicine
Paracetamol inhibits a metabolic pathway called cyclooxygenase 3, a phenomenon discovered at the beginning of the 21st century. This made it possible to explain the differences with respect to other non-steroidal anti-inflammatory drugs (NSAIDs), which were capable of inhibiting cyclooxygenase 1 and 2.
Since then, paracetamol has not been considered an NSAID, especially due to the absence of anti-inflammatory effects, compared to drugs such as ibuprofen.
2. Acetylsalicylic acid
Better known by the trade name of aspirin, this drug does belong to the group of NSAIDs. Its ability as an antipyretic is due to the inhibition of the cyclooxygenase pathway, which normally produces prostaglandins, which are essential to generate fever.
Despite its common use around the world, there are many interactions with other drugs that can reduce its effectiveness or cause adverse effects. Some medications that it may interact with are cyclosporine, vancomycin, methotrexate, digoxin, and the NSAIDs themselves.
Today, the main clinical indication for aspirin is as an antiplatelet agent. This term means that it prevents platelets from sticking together and forming a clot, which serves to stop bleeding. Clots are also involved in the pathophysiology of myocardial infarction and strokes.
The administration of a daily dose of this medicine, in patients with risk factors for the aforementioned conditions (such as hypertension, diabetes mellitus, obesity, and sedentary lifestyle) reduces its incidence and reduces mortality.
3. Ibuprofen as a therapy to lower fever
According to the World Health Organization (WHO), this drug is part of the list of essential drugs. It’s available over the counter and is quite inexpensive; it’s been on the market for decades. In fact, its chemical structure was discovered by the Spaniard Antonio Blancafort during an investigation led by a pharmaceutical company.
Regarding its mechanism of action to lower fever, it acts almost in the same way as acetylsalicylic acid, since it’s also part of the NSAID group. It is used as a treatment for rheumatoid arthritis and migraine, in combination with other analgesic substances.
Its role as a treatment for COVID-19
At the beginning of the pandemic, certain authors suggested, based on empirical observations, that the use of ibuprofen could be harmful in infected patients. This led many people to voluntarily discontinue their long-term treatments for conditions such as rheumatoid arthritis.
After that, several international organizations assured us that there was no evidence to support such claims.
This was announced by the Pan American Health Organization (PAHO) in a statement, in which it recommended patients with chronic diseases to continue with their usual treatment, and urged the rest of the patients with recent COVID-19 infection to use other NSAIDs or paracetamol, despite the lack of scientific evidence against ibuprofen.
4. Metamizole as a fever-reducing medicine
It was developed and marketed in Germany at the beginning of the 20th century, and became a success due to its obvious antipyretic, analgesic, and spasmolytic effects. This last term refers to the fact that it reduces or eliminates involuntary muscle contractions, related to the appearance of pain in diseases such as gallstones and kidney stones.
Its mechanism of action is similar to that of NSAIDs, despite the fact that it non-selectively inhibits the best-known cyclooxygenase pathways (1 and 2).
During the 1970s it was discovered that this drug may be capable of causing an adverse effect known as agranulocytosis. This implies the pathological decrease of several blood cells, especially neutrophils, which are part of the immune system and which allow the organism to be protected from bacterial infections.
Therefore, it was eventually withdrawn from the market of several developed countries due to the risk of developing such a complication.
In Spain, for example, the drug can only be obtained by prescription, and the Ministry of Health in that country issued a statement in which the specific indications for short and long-term treatments with metamizole are established.
Today, the discussion regarding its safety remains controversial, but there are several countries where it is still possible to purchase it without a prescription.
When do we have to go to the doctor?
If you have a fever, it is advisable to see a doctor as soon as possible, especially if it persists for several days. The causes are very varied, although it’s almost always due to infectious diseases.
Usually, there are associated symptoms that allow the doctor to make the diagnosis. Urination problems, a cough, a runny nose, low back pain, a severe headache, or the presence of skin lesions are some examples of classic infections in different parts of the body.
In some cases, the fever can be mistaken for a case of hyperthermia. This last condition is the transient elevation of body temperature as a result of other processes, such as intense exercise.
It isn’t the same as malignant hyperthermia, a serious illness that requires immediate hospitalization, and which usually occurs after the administration of anesthetics.
Useful and easily accessible drugs
Fever can be treated with a wide variety of medications, most of them belonging to the group of NSAIDs. Fortunately, there are few adverse reactions, as long as they are consumed in the recommended doses.
- Alcibar J, Gómez S, Vitoria Y, Jiménez A, Peña N, Oñate A, Cabrera A, Martínez P. Antitérmicos en pediatría. An Pediatr Contin. 2006;4:115-24.
- Benedi J. Antitérmicos. Farmacia Profesional 2007;21(3):50-58.
- Comité de Medicamentos de la Asociación Española de Pediatría. Pediamécum. Edición 2015. ISSN 2531-2464. . Disponible en: https://www.aeped.es/comite medicamentos/pediamecum/paracetamol-acetaminofen. Consultado el 21/01/2021.
- González M, et al. La aspirina. Revista Médica de la Universidad Veracruzana 2002;2(2):46-48.
Ramón-Romero F, et al. La fiebre. Revista de la Facultad de Medicina UNAM 2014;57(4):21-33.
Rodríguez A, Astobiza E, González M, Azkunaga B, Benito J, Mintegi S. Cambios de los hábitos poblacionales en el tratamiento de la fiebre en la infancia. An Pediatr (Barc). 2006;64:497-8.