Paracetamol

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Benjamin Clanner-Engelshofen is a freelance writer in the medical department. He studied biochemistry and pharmacy in Munich and Cambridge / Boston (USA) and noticed early on that he particularly enjoyed the interface between medicine and science. That is why he went on to study human medicine.

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Paracetamol is one of the most important active ingredients for pain and fever and is contained in numerous medications. The non-opioid pain reliever is well tolerated when used correctly. Pregnancy and breastfeeding are also not exclusion criteria for use. With the appropriate dosage, paracetamol can in principle be given at any age. Here you can read everything you need to know about the effects, side effects and use!

This is how paracetamol works

The exact mechanism of action of the pain reliever and fever drug is still unknown. Scientific studies have shown several potentially increasing effects on the body, which explain the analgesic and fever-lowering effect.

In contrast to the active ingredients acetylsalicylic acid and ibuprofen, which are also used as pain relievers and fever killers, paracetamol is not one of the so-called "acidic non-opioid analgesics". These tend to accumulate in the acutely inflamed tissue, in the mucous membrane of the gastrointestinal tract and in the kidney cortex and have good anti-inflammatory properties. Paracetamol, on the other hand, is a so-called "non-acidic non-opioid analgesic".

As such, it is not found in the body regions mentioned above, but in relatively high concentrations in the central nervous system (spinal cord and brain). There the active ingredient inhibits a certain sub-form of an enzyme (COX-3), which ensures the production of prostaglandins. These are tissue hormones that play a role in inflammatory processes, fever and the mediation of pain. Non-acidic, non-opioid analgesics such as paracetamol have poor anti-inflammatory effects, but good antipyretic effects.

Paracetamol also influences the endocannabinoid system, which mediates calming and analgesic effects, as well as the serotonin system. Serotonin is a messenger substance of the nervous system (neurotransmitter), which fulfills a variety of functions. Among other things, serotonin affects the cardiovascular system, blood clotting and the gastrointestinal tract and plays an important role in the brain as a "happiness hormone".

Researchers are still discussing the exact mechanism of action of the pain reliever and fever drug paracetamol.

The maximum concentration in the blood is reached after 30 to 60 minutes when the active ingredient is taken orally and after two to three hours when used rectally (suppositories). The time until half of the active ingredient is metabolized and excreted by the liver is one to four hours (half-life). The inactivated active ingredient is excreted via the kidneys.

When is paracetamol used?

Paracetamol is used for pain and fever, sometimes in combination with other pain relievers such as acetylsalicylic acid (ASA), codeine or tramadol.

Usually it is only used for a short time. In certain cases, however, the doctor can also prescribe long-term use.

This is how paracetamol is used

When used occasionally for mild to moderate pain, the active ingredient is mainly used in tablet form.

Paracetamol suppositories are especially suitable for use in children, toddlers and babies. These can usually be used without any problems. On the other hand, children often spit tablets out again. In addition, toddlers and infants are usually not yet able to take a tablet with a sip of water - they often choke on it. If suppositories are not tolerated, there is also a paracetamol juice.

There are special low-dose paracetamol preparations for the respective age groups. Paracetamol is used for colds and flu, especially because of its fever-lowering effect.

Doctors can also give their patients the active ingredient through the vein (paracetamol infusion solution). This is necessary, for example, in the case of severe infections with a high fever.

Combination preparations such as paracetamol plus ASA, paracetamol plus codeine or the triple combination of paracetamol, ASA and caffeine (for the treatment of tension headaches and mild migraines) have a better analgesic effect than the individual active ingredients.

What are the side effects of paracetamol?

Paracetamol side effects are relatively rare and mostly due to existing underlying diseases.

With low-dose, long-term use it can paradoxically happen that paracetamol causes headaches ("analgesic headache"). It must then be discontinued.

Liver damage is to be expected with high-dose, long-term ingestion as well as with a single paracetamol overdose. The liver can then no longer fulfill its task as a detoxification organ - one also speaks of paracetamol poisoning, which shows the typical signs of liver failure.

The maximum daily dose for adults without risk factors is three to four grams of paracetamol, depending on their weight. Doctors reduce the dose, especially for those with liver disease. Fatal courses have occurred from as little as seven grams.

Doctors treat acetaminophen poisoning with the active ingredient N-acetylcysteine ​​(the antidote of acetaminophen).

What should be considered when taking paracetamol?

The pain reliever and fever medicine must not be used in the case of severe liver and kidney damage, a certain enzyme deficiency (glucose-6-phosphate dehydrogenase deficiency) and excessive alcohol consumption (alcoholism). The same applies to known hypersensitivity (allergy) to the active ingredient.

During pregnancy and breastfeeding as well as in young patients (children), it is the first choice for short-term, low-dose use for the treatment of pain and fever without signs of inflammation. A doctor or pharmacist should be asked for advice on the use and dosage.

Paracetamol and alcohol

Since the active ingredient of paracetamol, like alcohol, is metabolized by the liver, there is a double burden on the detoxification organ in alcoholics and people who consume a lot of alcohol. This cannot always be compensated for and the pain reliever triggers liver failure. In general, alcohol should be avoided while using paracetamol.

How to get medicines with paracetamol

The pain reliever is available in Germany, Austria and Switzerland without a prescription in pharmacies up to a total of ten grams per medication pack (tablets). Paracetamol suppositories are not affected by this regulation due to the slower absorption of active ingredients.

Higher dose tablets and infusion solutions are subject to prescription requirements.

Since when has paracetamol been known?

Paracetamol-related substances have been studied since 1886 because of their analgesic and fever-lowering effects (acetanilide). On this basis, the US chemist Harmon Northrop Morse at Johns Hopkins University first produced the substance paracetamol in 1877. The optimization of the active ingredient from acetanilide via phenacetin to paracetamol was achieved through targeted further development of the molecular structure.

Paracetamol and phenacetin were first clinically tested in 1887 by the German physician Joseph von Mering. However, phenacetin was first found to be better, which is why paracetamol was forgotten for the time being. In 1947 David Lester and Leon Greenberg were able to show that phenacetin is metabolized to paracetamol and is just as effective as it.

Paracetamol was first marketed in the USA in 1953 - as a direct competitor to acetylsalicylic acid, which at the time was one of the few active ingredients for mild to moderate pain. Phenacetin, on the other hand, is no longer used today due to poor tolerance.

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