Clozaril
(clozapine)
Clozaril is used to treat schizophrenia in patients who have not been helped
by or are unable to take other medicines (treatment resistent patients).
Clozapine is effective for about 60 percent of those who try it. A patient
should try clozapine for at least four to six weeks. Some symptoms, such as
hallucinations, anxiety, paranoia, and bizarre behavior, should improve within
that time; other symptoms may take longer. Additional improvements may be
noticed over six to twelve months.
Benefits and Risks
Clozapine has unique benefits and unique risks. The benefits make it
a source of hope for the substantial number of patients with schizophrenia who
have not responded well to traditional antipsychotic medications. Although
clozapine use has certain risks, a careful monitoring system has been designed
to manage and minimize them.
Unique Risks of Clozaril
One to two percent of patients who take clozapine will develop a condition
called agranulocytosis, in which the white blood cell count drops dramatically.
The patient becomes extremely vulnerable to infections and unable to fight them
off. This condition is dangerous and potentially fatal. Fortunately, if
agranulocytosis does occur, most patients can be successfully treated by
stopping clozapine. In addition to stopping clozapine, hospitalization and
treatment with a drug that increases white blood cell production are available.
Agranulocytosis incidence with clozapine is over 10 times that of other
antipsychotics.
Clozaril is available only from pharmacies that agree to participate with
your doctor in a plan to monitor your blood tests. You will need to have blood
tests done every week for at least 6 months. After that, your doctor will
decide if it is safe for you to have blood tests every other week. You will
receive enough clozapine to last until your next blood test, but only if the
results of your blood tests show that it is safe for you to take this medicine.
If any of your blood tests are not normal, you may need to have blood tests
more often than every week until they return to normal.
Benefits of Clozaril
Unique effectiveness: In responsive patients, clozapine adds another
alternative to the traditional antipsychotics in treating the positive symptoms
of schizophrenia such as hallucinations, delusions, bizarre behavior and
hostility. It also effectively treats the negative symptoms— withdrawal,
blunted emotions, lack of motivation, and inability to experience pleasure or
enjoyment. It is the negative symptoms which seem to respond better to
clozapine than to the traditional antipsychotics.
Lack of usual side effects: Clozapine has virtually no incidence of
the muscle spasms, cramps, and posturing movements common to neuroleptic
(antipsychotic) drugs, and minimal incidence of the less serious neurological
side effects such as restlessness, muscle rigidity, and tremor (extrapyramidal
side effects or EPS).
Furthermore, clozapine does not seem to cause
tardive dyskinesia (TD), a disfiguring
side effect of standard antipsychotic drugs. TD is characterized by involuntary
movements such as grimacing, sucking and smacking of lips, and spasmodic
movements of the extremities. It usually begins after several months of
treatment and may be irreversible. There have been no confirmed cases of TD
directly caused by clozapine alone.
Do the benefits of clozapine outweigh the risks?
Clozapine poses a unique risk. Consequently, the FDA would not have approved
it unless its effectiveness was proven clearly superior to that of current
antipsychotic drugs. This was done conclusively in a 16-center study involving
over 300 severely ill patients. These patients had been ill for many years and
had failed to respond to at least three potent drugs.
In other studies of clozapine patients, 55 percent of previously
hospitalized patients were able to work at paying or volunteer jobs or return
to school, and re-hospitalization was reduced by 83 percent after 12 months.
This improvement in psycho-social functioning was largely due to clozapine
response.
Other risks associated with clozapine
Seizures may occur in roughly one to five percent of patients. The higher
the dose, the greater the risk of seizures. Cardiovascular and respiratory side
effects are also possible but extremely rare. Lowered blood pressure and
increased heart rate can usually be managed by gradually increasing a patient's
clozapine dosage from an initially low level. Some patients may notice weight
gain, drooling, and initial lethargy but can be managed by dose titration
(adjustment) or other interventions.
Additional Information
Risperdal ~ Clozaril ~
Zyprexa ~
Seroquel ~
Geodon
top
home
~ overview ~ comprehensive
info
meds ~
news stories ~
articles ~
bulletin board
|
