Quetiapine may cause numbness

Quetiapine

This is how quetiapine works

One of the central messenger substances (neurotransmitters) between the nerve cells in the human brain is dopamine. Through the release of dopamine, downstream nerve cells can pick up signals via certain selective docking points (receptors) which, in the case of dopamine, enable the feeling of motivation, joy, memory as well as learning, memory and targeted movements (fine motor skills).

Too much dopamine results in excessive, manic pleasure up to schizophrenia and a loss of reality. To get this excessive dopamine effect under control, antipsychotic drugs such as quetiapine are used. Quetiapine binds to dopamine receptors in the brain without activating them, so it simply blocks them for the dopamine, which is actually present in high concentrations. As a result, the dopamine effect is regulated down to normal values, whereby the patient can be brought back to reality.

Uptake, breakdown and excretion of quetiapine

After being absorbed in the intestine, quetiapine is extensively metabolized in the liver, although the breakdown products also have an antipsychotic effect. After about seven hours, half of the active ingredient (after twelve hours half of the active breakdown product) is excreted - three quarters with the urine and one fourth with the stool.

When is quetiapine used?

The active ingredient is used in the treatment of schizophrenia and bipolar disorder. In the latter, quetiapine is used in particular to treat manic episodes and severe depressive episodes in the course of the disease. It is also used to prevent relapses in such episodes if they have previously responded to the drug.

Quetiapine is used in higher doses for acute treatment; Lower doses are used for long-term maintenance therapy.

This is how quetiapine is used

The active ingredient quetiapine is mainly used in the form of tablets. In order to avoid multiple dosing at higher dosages, which is important for constant blood levels, tablets with delayed release of active ingredients (retard tablets) are on the market.

There are different dosage regimens depending on the area of ‚Äč‚Äčapplication. What they all have in common is that for the initial treatment of acute psychological complaints, the active ingredient is "crept in" over a few days - treatment is started with a very small dose and then over several days to the full final dose that achieves the desired quetiapine effect , increased. For maintenance therapy, the amount of active ingredient is then reduced to the lowest effective dose.

The active ingredient is taken once or twice a day, regardless of meals, according to the doctor's instructions.

What are the side effects of quetiapine?

The most common (in more than one in ten people treated) quetiapine side effects are drowsiness, dizziness, dry mouth, headache, withdrawal symptoms (when stopping treatment), increased blood lipid levels, increased total cholesterol (predominantly LDL cholesterol), decreased HDL cholesterol, weight gain and so-called extrapyramidal symptoms (Parkinson-like side effects).

In addition, every hundredth to tenth person treated with quetiapine experiences side effects such as changes in thyroid hormone levels, increased blood sugar levels, increased appetite, abnormal dreams and nightmares, suicidal behavior, blurred vision, palpitations, shortness of breath and indigestion.

What should be considered when taking quetiapine?

Quetiapine works primarily in the central nervous system, which is why the intake of other centrally active active ingredients should be clarified beforehand and only with caution. The same applies to the consumption of alcohol.

The active ingredient is mainly broken down by the so-called CYP enzyme system in the liver, which also breaks down many other drugs in the body. In particular, the enzyme CYP3A4, which metabolizes quetiapine, also breaks down many other active substances. If these are taken at the same time, one active ingredient is usually broken down with priority, while the other builds up in the body. The possible consequence is an undesirably high concentration and even toxicity.

When taken at the same time, other active ingredients ensure that quetiapine is broken down more quickly and therefore has poor or no effect. Examples of such drugs are ketoconazole (for fungal infections) and carbamazepine and phenytoin (for epilepsy).

Treatment with quetiapine is not recommended in children and adolescents under 18 years of age as no data are available.

Elimination from the body is slower in the elderly, so the dose should be reduced so that the active substance does not build up in the body. The same applies to patients with impaired liver function.

pregnancy and breast feeding period

Since the safety of taking quetiapine during pregnancy has not been proven, pregnant women should not take the active ingredient. It also passes into breast milk, which is why breastfeeding mothers should also not take the active ingredient. If ingestion is absolutely necessary, breastfeeding should be discontinued.

How to get quetiapine medication

Quetiapine is only available on prescription in any dosage and only after presentation of a prescription at the pharmacy.

How long has quetiapine been known?

The active ingredient was discovered and researched by the pharmaceutical company AstraZeneca between 1992 and 1996 as a further development of the first generation of antipsychotics (the typical neuroleptics). In 1997 he received his license in the USA. The patent expired in 2012: since then, numerous generics with the Active ingredient quetiapine on the market.

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