Clozapine Ampicillin

The authors suspected that, since the prescribed antibiotics (trimethoprim, sulfamethoxazole, and ampicillin) did not seem to be responsible for the large rise in serum clozapine concentrations, the rise might have been secondary to cytokine-mediated inhibition of cytochrome P450. 

Csik V, Molnar J. Possible adverse interaction between clozapine and ampicillin in an adolescent with schizophrenia. J Child Adolesc Psychopharmacol 1994 4 123-8. 

Ampicillin, cefotaxime, ceftazidine, ciprofloxacin, methicillin, sulfathiazole, sulfamethoxazole Carbamazepine, felbamate, mesantoin, phenytoin, valproic acid Cimetidine, ranitidine Amodiaquin, chloroquine, quinine Chlorpromazine, clozapine, mianserin... 

There are isolated cases of apparent interactions between clozapine, and ampicillin, buspirone, caffeine, haloperidol, loperamide, modafinil, nefazodone, nicotinic acid, tryptophan, or vitamin C. Grapefruit juice, influenza vaccine mirtazapine, reboxetine, or venlafaxine do not appear to interact Cocaine levels may increase when taken with clozapine. 

An isolated report describes a 17-year-oid taking clozapine (12.5 mg increased to 50 mg three times daily) who was given ampicillin 5(X) mg four times daily, starting on day 15 of clozapine treatment. On the next day the patient became easily distracted, very drowsy and salivated excessively. These adverse reactions stopped when the ampicillin was replaced by dox-ycycline. ... 

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