Clozapine represents a breakthrough anti-psychotic medicine. Clozapine was introduced to the United States market in 1990 and is on the World Health Organization of essential medicines. Not only does Clozapine treat schizophrenia and related conditions, but it appears more effective than the standard anti-psychotic therapies. Clozapine also improves resistant schizophrenia and may additionally reduce the risk of suicide in these individuals.

Due to safety concerns that originated in Finland, the use of Clozapine has decreased. Current practitioners lack familiarity with this drug, and as a result of some negative publicity seem disinclined to prescribe it.

The two most worrisome issues involve a decline, sometimes serious, in the number of bacteria fighting neutrophils – a type of white blood cell. This occurs in about 3% of exposed individuals most commonly in the first 4 months of therapy. During this phase of Clozapine therapy, most recommend weekly laboratory tests.

Perhaps even more troublesome is a slowing of movement of muscular activity of gastrointestinal tract. This may lead to constipation, fecal impaction and bowel obstruction. Pre-emptive therapy with laxatives minimizes this issue. Other adverse drug reactions may occur.

In spite of the side effect profile, a recent study ranked Clozapine as the most effective drug in its class. As a generic, the financial burden it poses is minimal and more akin to the generic versions of Abilify, Zyprexa and Risperdal.