Benserazide

Benserazide is an active ingredient that is not available as a single preparation, but is always administered in combination with levodopa. Both active ingredients are prescribed exclusively for the treatment of Parkinson's and Restless Legs Syndrome. Benserazide supports the prodrug levodopa so effectively because it works directly on the periphery.

What is benserazide

Benserazide (chemical formula: C10H15N3O5) occurs as benserazide hydrochloride only together with levodopa. It is a white to yellowish, crystalline, water-insoluble powder. It belongs to the group of benserazide decarboxylase inhibitors. As the name suggests, it blocks the action of dopamine decarboxylase, an enzyme that breaks down the neurotransmitter dopamine in the blood and intestines.

Benserazide cannot cross the blood-brain barrier and only has a peripheral effect (i.e. outside the central nervous system). It prevents L-dopa from being broken down at the periphery and thus ensures that the dopamine precursor can cross the blood-brain barrier and produce the urgently needed dopamine in the brain.

In the tablets to be taken orally against Parkinson's disease and Restless Legs Syndrome, both active substances are represented in a ratio of 4: 1 (L-dopa: benserazide). They are sold under the trade names Madopar®, Levopar® and Levodopa comp.® and contain doses of 100 mg / 25 mg, 200 mg / 50 mg and 50 mg / 12.5 mg.

Pharmacological effect

Benserazide, together with levodopa, helps to relieve the symptoms typical of Parkinson's disease - tremors (tremor), rigid muscles (rigidity) and disturbed movements (akinesia), to give the person more freedom of movement and to slow the progression of the disease.

Since the neurotransmitter dopamine, which effectively reduces these symptoms, cannot cross the blood-brain barrier itself, it is administered in the form of its precursor (L-Dopa). This active ingredient, in turn, is largely broken down in the body by an enzyme, dopamine decarboxylase, before it can get to where it is needed to produce more dopamine (the brain). Since the patient would have to be given too high doses of L-Dopa in order for any of the active substance to reach the brain at all, it is administered together with benserazide.

Benserazide hydrochloride inhibits the activity of the L-dopa-degrading enzyme very effectively, because it can bind to the enzyme due to its molecular similarity to levodopa and deactivate its catalytically active center. L-Dopa is able to cross the blood-brain barrier unhindered and in full dose.

Another pharmacological effect of benserazide is that it prevents the release of prolactin in breastfeeding women. This hormone is responsible for the production of breast milk.

Medical application & use

The combination preparation levodopa + benserazide is indicated for long-term therapy in patients with Parkinson's disease and restless legs syndrome. It is also used in people who show symptoms similar to Parkinson's, although these must not be a side effect of an administered drug.

Parkinson's patients regain their mobility at least partially through the active ingredients. In addition, the rapid progression of the disease is inhibited. Restless legs syndrome, which is apparently also due to a dopamine deficiency in the brain, alleviates the symptoms that occur in bed at night (uncontrollable need to move, abrupt pain and muscle twitching). The patients find rest at night.

In addition, the active ingredient combination levodopa + benserazide is used to diagnose the "restless legs syndrome": If the symptoms are noticeably alleviated, the person affected actually suffers from this disease. For this purpose, the doctor usually administers the preparation in the form of tablets of 100 mg / 25 mg. The combination agent can also be easily combined with other approved drugs against Parkinson's disease.

You can find your medication here

Risks & side effects

When taking levodopa + benserazide in the indication of Parkinson's disease, the following side effects are very common: loss of control over the mouth, tongue and head, impaired body movements, urine discoloration, nausea and vomiting. Fears, depression, agitation, confusion, drowsiness, insomnia, loss of appetite, sweating, tremors, fatigue, indigestion, dry mouth and stomach pain are often observed.

Restless Legs Syndrome Patients who have been prescribed the drug are very likely to experience insomnia, depression, diarrhea, nausea and vomiting. Changes in taste, hallucinations, anxiety and cardiac arrhythmias are common.

Levodopa + benserazide should not be used if the patient is hypersensitive to the active ingredients, a pheochromocytoma (adrenal gland tumor), severe hyperthyroidism, psychosis, palpitations, narrow-angle glaucoma, or severe liver, heart, kidney, metabolic and bone marrow diseases or is under 25 years of age.

It should also not be given during pregnancy. Embryonic damage was found in animal experiments. No medical data are yet available for humans. Breastfeeding women should definitely stop breastfeeding if they need to take the product.

It is only given to people with previous gastrointestinal ulcers, heart attacks, coronary heart disease, arrhythmias, wide-angle glaucoma, bone softening, and diabetes if there is an urgent medical indication. You will be checked regularly by a doctor during treatment.

If the combination of active ingredients against Parkinson's disease and Restless Legs Syndrome is administered together with painkillers (opiates), neuroleptics, iron preparations, acid-binding drugs (antacids), phenytoin, papaverine, antihypertensive and circulatory drugs, its effectiveness is reduced.

The effect of levodopa + benserazide is increased if the drug is taken with selective MAO-B inhibitors. For example, it may be necessary to adjust the Amantadine or Selegelin dose. MAO-A inhibitors should be discontinued 14 days before taking levodopa + benserazide, as otherwise the patient may experience a critical rise in blood pressure.The stomach drug metoclopramide ensures faster absorption of the active substances and more side effects.