Allopurinol is used to treat chronic gout disease. The active ingredient ensures that the uric acid concentration in the blood is lowered. As a result, the drug can prevent an acute attack of gout. Allopurinol is considered to be well tolerated, but side effects may occur during use. The most common complaints include gastrointestinal problems and allergic skin reactions. Learn details about the effects, side effects, and dosage of allopurinol here.
Effect of allopurinol on gout.
Uric acid plays a crucial role in the development of gout. It is formed during the breakdown of purines. Purines are produced on the one hand by the body itself, on the other hand they enter the body through purine-rich foods such as meat, certain types of fish as well as legumes. If there is too much uric acid in the body (hyperuricemia), uric acid crystals form. These are insoluble in water and can therefore be deposited in the tissue. This can lead to the typical gout symptoms such as painful thickening and inflammation in the joints. Allopurinol is one of the so-called uricostatic drugs that inhibit the breakdown of purines into uric acid. This is done by the active ingredient blocking a specific enzyme (xanthine oxidase) that is needed for the breakdown. If the purines can no longer be broken down to uric acid, the uric acid level in the blood drops. In addition, existing deposits in the tissue can be broken down. Instead of uric acid, taking the active ingredient produces more xanthine – a precursor of uric acid that can be excreted from the body much more quickly via the kidneys. In the case of gout, allopurinol is recommended above a uric acid concentration of 8.5 milligrams/100 milliliters of blood. In addition to gout, the active ingredient is also used to treat other diseases. For example, it is used to treat uric acid-induced damage to the kidneys or secondary hyperuricemia. Likewise, it is used to treat certain enzyme deficiency disorders associated with elevated uric acid levels.
Side effects of allopurinol
The active ingredient is generally considered to be well tolerated, but side effects may still occur while taking allopurinol. For example, an acute attack of gout can be triggered by the drug at the beginning of therapy. In addition, nausea, nausea and diarrhea may occur. Allergic skin reactions such as itching, redness and swelling are also possible. If you experience skin reactions, please contact your doctor immediately and discuss with him whether the intake should be continued. In individual cases, the active ingredient can cause severe skin reactions associated with scaling and peeling of the skin. These may be symptoms of a life-threatening skin reaction such as occurs in Stevens-Johnson syndrome or epidermal necrolysis. In rare cases, other side effects may occur while taking allopurinol. These include headache, fever, joint pain, seizures, and kidney inflammation. Since dizziness, drowsiness, and movement disorders are also possible side effects, do not drive a car or work on an electric machine after taking the drug. Also, avoid activities where you do not have a firm grip.
Dosing allopurinol correctly
Allopurinol is taken in the form of tablets. The tablets contain either 100 or 300 milligrams of allopurinol. Usually, 100 milligrams is started and the dose is then slowly increased as needed. In individual cases, the daily dose may be increased to 600 to 800 milligrams. The tablets should be taken unchewed with plenty of liquid after meals. If you take more than 300 milligrams or if you experience gastrointestinal symptoms, you should spread the dose over the day. It is important to check uric acid levels regularly during treatment and adjust the dose if necessary. In children, the maximum daily dose is 400 milligrams. In general, children should not take more than 10 milligrams of allopurinol per kilogram of body weight per day. This involves dividing the total dose into three individual doses, taken in the morning, at noon, and in the evening.
Contraindications: Not for pregnant women
Although allopurinol is well tolerated, you should still not use the active ingredient under certain circumstances. This is the case, for example, if there is hypersensitivity to the active substance.Pregnant women should also refrain from taking the drug, as there has not been sufficient experience with it to date. The active substance is also contraindicated during breastfeeding, as it passes into breast milk. If you have certain diseases, special precautions must be taken: For example, in the case of a blood formation disorder, regular checks of the blood count must be carried out. On the other hand, if you have kidney disease, the dose taken must be reduced. This is because allopurinol is excreted by the kidneys and the retention time in the body is prolonged in the case of kidney disease. The dose may also need to be adjusted if liver function is impaired. Caution: please note that allopurinol is only suitable for the prevention of a gout attack, not for its acute treatment! If allopurinol is taken during a gout attack, more uric acid crystals may be formed. This may prolong or worsen the attack.
Drug Interactions
If allopurinol is taken with certain other medications, interactions may occur. For example, the effect of the gout medicine is decreased by agents such as benzbromarone, etacrynic acid, probenecid, sulfinpyrazone, and thiazines. Chlorpropamide, ciclosporin, phenytoin and theophylline, on the other hand, enhance the effect of allopurinol, as do coumarin-type anticoagulants. Allopurinol itself also influences other drugs. Thus, it enhances or prolongs the effect of drugs containing chlorpropamide, phenprocoumon, salicylic acid, theophylline, and vidarabine. Anticoagulants may also be enhanced in their effect. In contrast, allopurinol slows the excretion of probenecid. The active substance should also not be taken together with antibiotics such as ampicillin or amoxicillin. Otherwise, skin rashes may occur. The gout medicine should also not be combined with cytostatics, as this can lead to changes in the blood count. If cytostatics have to be taken, a significant reduction in the dose is usually necessary. A detailed list of all side effects, contraindications, and interactions of and with allopurinol can be found in the package insert of your medication.
Instructions for taking allopurinol.
You can support therapy with allopurinol by following these behaviors:
- Eat a balanced and healthy diet. Refrain from purine-rich foods such as offal, legumes, fish or alcohol.
- Drink plenty, preferably water or herbal teas.
- Try to reduce your weight a little if you are overweight.
