Olanzapine is an atypical neuroleptic. The active ingredient is used to treat schizophrenic psychosis.
What is olanzapine?
The drug olanzapine is classified as an atypical neuroleptic. It is among the most important drugs used to treat schizophrenia. Unlike older neuroleptics, olanzapine has better tolerability. The active ingredient is considered relatively young. It originated from classic neuroleptics and was developed in the 1990s to treat psychological complaints. Olanzapine was launched in Germany in 1996 under the trade name Zyprexa. The active ingredient belongs to the second generation of neuroleptics and triggers fewer side effects. However, a strong increase in weight is possible. Since 2012, there are also some generics of olanzapine.
Pharmacologic effects on the body and organs
The fact that a person feels balanced and can react appropriately to certain situations, such as fear, joy or excitement, is made possible by the interaction of several neurotransmitters that act within the brain and spinal cord (which form the central nervous system (CNS)). This results in the release of neurotransmitters such as dopamine and serotonin. Later, the uptake and storage of these neurotransmitters occurs. In the case of schizophrenia, there is a disturbance in the balance of neurotransmitters. The effect of olanzapine is based on the blockade of receptors (binding sites) of the neurotransmitter dopamine. In this way, typical symptoms of schizophrenia such as delusions or hallucinations can be alleviated. Furthermore, the neuroleptic occupies the binding sites of the neurotransmitter serotonin, which in turn has a positive effect on the apathy of the patients. This improves concentration and memory, while depression is reduced. Olanzapine also calms the patient slightly and counteracts mania, in which the drive is temporarily greatly increased. As a dopamine antagonist, olanzapine inhibits the action of dopamine. However, only 40 to 60 percent of this occurs in the loop body (striatum). For this reason, it causes fewer extrapyramidal motor disorders (EPS) than older neuroleptics. In terms of side effects, olanzapine forms a weaker version of clozapine. After ingestion by mouth, the drug can easily enter the blood within the intestine. Once olanzapine has spread throughout the body, it is broken down in the liver. Excretion of the active ingredient takes place largely through the kidneys.
Medical use and use for treatment and prevention.
The most important application of olanzapine is in the treatment of psychosis manifested in schizophrenia or manic illness. The drug is particularly well suited for patients who no longer have a connection to reality and who therefore have severe states of agitation, severe depression, and anxiety disorders. Olanzapine can also be used to treat hallucinations, delusions, personality disorders and aggressive behavior. Other areas of use include bipolar disorders and suicidality. The drug is usually taken orally by tablets. In acute cases, however, there is also the possibility of an injection into the blood. The recommended daily dose is 10 milligrams. If necessary, it can be increased step by step to 20 milligrams per day. The patient usually takes the olanzapine once a day, which is done independently of meals. Towards the end of therapy, discontinuation of the active substance should take place slowly to avoid symptoms such as anxiety, insomnia, tremors, nausea, vomiting and sweating. However, olanzapine can only develop its full positive effect after a few days or even weeks.
Risks and side effects
Adverse side effects occur in about 10 percent of all people treated with olanzapine. These primarily include weight gain and drowsiness. About 1 to 10 percent of patients experience dizziness, dry mouth, low blood pressure, and constipation. Other common side effects include increased blood sugar levels, disturbances in fat metabolism, impaired movement control and the release of the hormone prolactin. This stimulates the formation of milk in the mammary glands. Increased prolactin levels can be manifested by enlarged breasts, feelings of tension and the secretion of milk.In some cases, problems with urination, difficulty sitting still, twitching or tics, loss of appetite, nausea, vomiting, heartbeat that is too slow or too fast, fluctuations in pulse and blood pressure, the drop in blood pressure after standing up, liver dysfunction, the formation of edema in the tissues, blood formation disorders in the bone marrow, and increased sensitivity to light also become apparent. If the patient abruptly discontinues olanzapine, there is a risk of symptoms such as severe nausea, tremors, sleep problems, sweating, and anxiety disorders. There are also some contraindications to olanzapine. For example, the drug cannot be administered if the patient suffers from glaucoma with increased intraocular pressure. Injection of the drug into a muscle should be avoided in cases of angina pectoris, severe hypertension, pronounced weakness of the heart muscle, slow heartbeat (bradycardia), excitation conduction disorders in the heart, and after heart surgery or a heart attack. Greater caution is advised in case of liver dysfunction, diabetes mellitus, intestinal paralysis, benign enlargement of the prostate and if the patient is prone to seizures. Olanzapine should not be administered during pregnancy and lactation. The safety of the active substance for mother and child could not be proven. It is also recommended that contraception be used consistently during olanzapine therapy. In the last trimester of pregnancy, the unborn child is at risk of side effects such as withdrawal symptoms and movement disorders if the neuroleptic is taken. In such cases, careful medical monitoring must take place.
