What is Farlin Metamizole Sodico

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Metamizole, also known as Novaminsulfon, is one of the most important active ingredients for severe pain, high fever and cramps. The active ingredient is found in medicines as salt (metamizole sodium). This is very soluble in water and can therefore be administered via an infusion as an emergency medication even in the case of acute illness symptoms. But there are also metamizole drops and tablets. Here you can read everything you need to know about metamizole.

This is how metamizole works

Pain is part of the vital protection and warning system of the human body. In the event of injuries, the concentration of certain messenger substances (prostaglandins) increases in the tissue. If these bind to their docking points (receptors), the nervous system forwards signals to the brain. These are processed there and as a result you feel pain.

Metamizole is converted into its actually active form in the body and as such inhibits the production of special prostaglandins, mainly in the brain and spinal cord (central nervous system). This prevents the development of pain and, as a result, the perception of pain.

The fever-lowering effect of metamizole is based on an influence on the temperature regulation center in the brain.

The release of spasms (spasmolysis) presumably comes about by inhibiting the transmission of stimuli to the so-called smooth muscles (gastrointestinal tract, urinary tract, uterus).

Metamizole uptake, breakdown and excretion

When taken by mouth (orally), the active ingredient metamizole is still converted in the intestine. The resulting active compound is then completely absorbed into the blood and develops its maximum effect after approximately one and a half hours. The substance is metabolized in the liver and finally excreted via the kidneys.

If metamizole sodium is administered via an infusion, the effects are immediate. The further breakdown in the liver and excretion via the kidneys proceed as with oral ingestion.

When is metamizole used?

The areas of application (indications) of metamizole include:

  • Severe pain, including tumor pain
  • High fever

This is how metamizole is used

The usual dose of metamizole (oral or infusion) is approximately 0.5 to one gram per day in adults. If necessary, the dose can be increased to up to four grams per day. The dose must be reduced in children and patients with impaired liver or kidney function.

In addition to metamizole drops, the active ingredient is also available in the form of infusion solutions, tablets and suppositories.

When administering as an infusion, it should be ensured that the administration is not carried out too quickly so that there is no shock.

What are the side effects of metamizole?

The active ingredient is usually well tolerated. Possible side effects of metamizole are, for example, allergic reactions of the skin and a drop in blood pressure (hypotension). These side effects occur occasionally, i.e. in 0.1 to one percent of those treated. Less often there is a severe deficiency of a certain subgroup of the white blood cells, the granulocytes. Possible signs of this so-called agranulocytosis are sudden fever, inflammatory changes in the lining of the mucous membrane and a sore throat. If any of these symptoms occur, metamizole sodium should be discontinued immediately and the blood count should be checked by the attending physician.

What should be considered when taking metamizole?


In asthma patients, taking metamizole can trigger asthma attacks. You must therefore not receive any medication with this active ingredient. The same applies to patients with a certain enzyme deficiency (glucose-6-phosphate dehydrogenase deficiency) or disorders of the bone marrow function.


Metamizole can reduce the concentration of ciclosporin in the blood and thus its effectiveness. Therefore, caution is advised when taking the two drugs at the same time. Ciclosporin is used in autoimmune diseases and after organ transplants to suppress the immune system.

pregnancy and breast feeding period

The use of metamizole during pregnancy and breastfeeding should be avoided, as very little experience has been gained in this regard. Instead, better tried-and-tested alternatives should be used (paracetamol for pain and fever, ibuprofen for inflammatory diseases).

Age restrictions

Infants under 3 months of age or weighing less than five kilograms should not be given the active ingredient, as insufficient data are available to ensure safe treatment.

How to get medicines with metamizole

Medicines containing metamizole require a prescription and can only be obtained from a pharmacy with a prescription from a doctor.

Since when has metamizole been known?

Metamizole has been used in Germany for over ninety years (first registration in 1922). Since then, the drug has been criticized again and again because of the possible side effect "agranulocytosis". Estimates of the frequency of these side effects vary widely: some experts estimate that one in 2,000 people treated will develop agranulocytosis, while other experts assume only one person in every 1,500,000 people treated.

However, the active ingredient has clear advantages over other pain relievers. On the one hand, it does not have a blood-thinning effect, which can be of great importance especially for patients at risk of falling. On the other hand, metamizole does not damage the gastric mucosa or impair kidney function, as is the case with many other pain relievers (analgesics).

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