Review question

To determine the effectiveness of benzodiazepines in the treatment of tardive dyskinesia in people with schizophrenia or other similar mental health problems.

Background

People with schizophrenia often hear voices and see things (hallucinations), and have strange beliefs (delusions). The main treatment for schizophrenia is antipsychotic drugs. However, these drugs can have debilitating side effects. Tardive dyskinesia is an involuntary (uncontrollable and unintended) movement that causes the face, mouth, tongue, and jaw to convulse, spasm, and grimace. It is caused by prolonged or high-dose use of antipsychotic drugs, is difficult to treat, and can be incurable. The benzodiazepine group of medicines have been suggested as a useful add-on treatment for tardive dyskinesia. However, benzodiazepines are very addictive.

Study characteristics

The review includes four clinical trials with 75 people who had tardive dyskinesia as a result of using antipsychotic medicines. The participants were randomised into groups that received either their usual antipsychotic medicine plus a benzodiazepine or their usual antipsychotic plus a placebo (dummy medicine).

Key results

Improvement in TD symptoms was similar between the treatment groups. Participants were just as likely to leave the studies early from the placebo groups as the benzodiazepine groups. Data were not available for outcomes important to patients such as improvement in social confidence, social inclusion, social networks or quality of life.

Quality of the evidence

Evidence is limited because the trials are so few, small, and poorly reported. It is uncertain whether benzodiazepines are helpful in the treatment of tardive dyskinesia. The use of benzodiazepines for treating people with antipsychotic-induced TD therefore remains experimental, and because they are highly addictive, a last resort. The low number of studies in this review strongly indicates that this is not an active area of research. To fully investigate whether benzodiazepines have any positive effects for people with tardive dyskinesia, there would have to be more well-designed, conducted and reported trials.

This plain language summary was adapted by the review authors from a summary originally written by Ben Gray, Senior Peer Researcher, McPin Foundation (mcpin.org/).