Metaclazepam is a drug which is a benzodiazepine

Benzodiazepine

A benzodiazepine is a psychoactive drug whose core chemical structure is the fusion of a benzene ring and a diazepine ring...

 derivative. It is a relatively selective anxiolytic

Anxiolytic

An anxiolytic is a drug used for the treatment of anxiety, and its related psychological and physical symptoms...

 with less sedative

Sedative

A sedative or tranquilizer is a substance that induces sedation by reducing irritability or excitement....

 or muscle relaxant

Muscle relaxant

A muscle relaxant is a drug which affects skeletal muscle function and decreases the muscle tone. It may be used to alleviate symptoms such as muscle spasms, pain, and hyperreflexia. The term "muscle relaxant" is used to refer to two major therapeutic groups: neuromuscular blockers and spasmolytics...

 properties than other benzodiazepines such as diazepam

Diazepam

Diazepam , first marketed as Valium by Hoffmann-La Roche is a benzodiazepine drug. Diazepam is also marketed in Australia as Antenex. It is commonly used for treating anxiety, insomnia, seizures including status epilepticus, muscle spasms , restless legs syndrome, alcohol withdrawal,...

 or bromazepam

Bromazepam

Bromazepam is a benzodiazepine derivative drug, patented by Roche in the 1963 and developed clinically in the 1970s...

. It has an active metabolite

Active metabolite

- Prodrugs :Sometimes drugs are formulated deliberately so they will break down inside the body to form the active drug, these are called prodrugs. The reason for this may be because the drug is more stable during manufacture and storage as the prodrug form, or because the prodrug is better...

 N-desmethylmetaclazepam, which is the main metabolite

Metabolite

Metabolites are the intermediates and products of metabolism. The term metabolite is usually restricted to small molecules. A primary metabolite is directly involved in normal growth, development, and reproduction. Alcohol is an example of a primary metabolite produced in large-scale by industrial...

 of metaclazepam. There is no significant difference in metabolism between younger and older individuals.

Metaclazepam is slightly more effective as an anxiolytic than bromazepam

Bromazepam

Bromazepam is a benzodiazepine derivative drug, patented by Roche in the 1963 and developed clinically in the 1970s...

, or diazepam

Diazepam

Diazepam , first marketed as Valium by Hoffmann-La Roche is a benzodiazepine drug. Diazepam is also marketed in Australia as Antenex. It is commonly used for treating anxiety, insomnia, seizures including status epilepticus, muscle spasms , restless legs syndrome, alcohol withdrawal,...

, with a 15 mg dose of metaclazepam equivalent to 4 mg of bromazepam. Metaclazepam can interact with alcohol producing additive sedative-hypnotic effects. Fatigue is a common side effect from metaclazepam at high doses. Small amounts of metaclazepam as well as its metabolites enter into human breast milk

Breast milk

Breast milk, more specifically human milk, is the milk produced by the breasts of a human female for her infant offspring...

.