The effects of drugs that can cause CNS depression or lower bloodpressure may possibly be increased by presence of procarbazine
Clinical evidence,mechanism, importance and management
In one early clinical study,4 of 48 patients developed postural hypotension when treated with procarbazine. In addition,another patient with hypertension (180/110 mmHg) had a progressive fall in blood pressure (to 110/80 mmHg) while being treated with procarbazine (See reference number 1). Additive hypotensive effects may therefore be expected if procarbazine is given to patients taking antihypertensives.
Procarbazine can cause CNS depression ranging from mild drowsiness to profound stupor. In early clinical studies, incidence was variously reported as 8%, 14%, and 31 % (when combined with prochlorperazine, see also (c) below) (See reference number 1-3). Additive CNS depression may therefore be expected if other drugs possessing CNS-depressant activity are given with procarbazine.
An isolated report describes an acute dystonic reaction (difficulty in speaking or moving, intermittent contractions of muscles on left side of neck) in a patient taking procarbazine with prochlorperazine (See reference number 4). Prochlorperazine was thought to have contributed to sedative effects of procarbazine in one early clinical study (See reference number 3).
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