Antipsychotics - Drugs against Schizophrenia

by Pontus Strålin, MD, PhD

Treatment to help the individual
The aim of psychiatric treatment of schizophrenia is to help the individual with the disease to function as good as possible in his social life and in vocation, and that the subjective well-being is strengthened.
The treatment is individualised and usually contains some of the following aspects: medication, social support, individual psychotherapy, family education and family support.

Antipsychotics (neuroleptics)
The treatment with drugs is most often a cornerstone. The drugs used are called antipsychotics, or with another word, neuroleptics. Scientific research has shown that antipsychotics are effective in preventing relapses into psychosis.
There are a number of different antipsychotic drugs available for the treatment. They may be roughly categorised into two groups: conventional and atypical.

Conventional antipsychotic drugs
The conventional antipsychotic drugs have been in use since many decades and the clinical experience of them is very big. The group includes drugs such as haloperidole (Haldol), zuclopenthioxol (Cisordinol), perphenazin (Trilafon), alimemazin (Theralen) and chlorpromazine (Hibernal). These drugs are effective primarily against positive symptoms of schizophrenia such as hallucinations and formal thought disturbances. They thus have a good preventing effect against relapse of psychosis. At high doses, side effects are common. These include the so-called extrapyramidal symptoms such as tremor, muscle stiffness and unintended movements, as well as an experience of unrest and inability to be still. Often a low dose where no side effects are seen is sufficient for a good effect.

Atypical antipsychotic drugs
Most of the atypical antipsychotic drugs have appeared in the later years. This group include risperidone (Risperdal), olanzapin (Zyprexa), clozapin (Leponex) and Zeldox. The drugs in this group share the good preventing effect against psychosis with the conventional drugs, but the risk of developing the extrapyramidal side effects is probably smaller. There is also scientific evidence pointing to a profitable effect of these drugs on negative symptoms and improved cognitive function. Clozapin often has a good effect where other antipsychotic drugs have failed. A drawback of this drug is that the production of white blood cells in the bone marrow may be inhibited in a small share of individuals treated. For this reason, blood samples must be taken regularly as a control measure.

Side effects
For both groups of antipsychotic drugs, but particularly the atypical, there is a risk for weight gain as a side effect. A number of other side-effects may occur. On suspicion of a side effect, the responsible physician should be consulted.

Pills, mixture or injections
Antipsychotic drugs may be administered as pills, mixture or injections. The most common forms are the pills and the depot injections. The depot injections are made with a preparation of drug that is injected and then slowly released into the body during some weeks. This preparation is often a good choice for example if there is a difficulty for the individual to remember to take the pills. No daily attention to medication is needed. Depot preparations are currently available only for conventional antipsychotic drugs (in Sweden).

Choice of antipsychotic drug
The choice of an antipsychotic drug for the individual patient is influenced by the current symptoms and side effects among other factors. It is often difficult to predict which drug will give the best effect. For this reason it is often necessary to make some changes the drug therapy due to an unsatisfying effect or troublesome side-effects.

Act by modulating the signalling systems in the brain
Antipsychotic drugs act by modulating the signalling systems in the brain. The basic mechanism of conventional antipsychotic drugs is to reduce the effects of dopamine. This is achieved by a partial blockade by the drug molecules of the so-called D2 receptors on the dopamine-responding cells. The atypical antipsychotic drugs act both on the dopamine system, the serotonin system, and on other signalling systems in the brain.

Information about Antipsychotics