Chloroquine and Tagamet HB

In the database of official manuals used in the service creation an interaction registered by statistical results of studies was found, which can either lead to negative consequences for the patient health or strengthen a mutual positive effect. A doctor should be consulted to address the issue of joint drug administration.

Talk to your doctor before using chloroquine together with cimetidine. Combining these medications may increase the blood levels of chloroquine. This may increase the risk of side effects such as headache, nausea, vomiting, diarrhea, abdominal cramps, loss of appetite, vision impairment, ringing in the ears, hearing loss, anxiety, confusion, depression, and seizures. Your doctor may be able to prescribe alternatives that do not interact. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

GENERALLY AVOID: Coadministration with cimetidine may increase the plasma concentrations of chloroquine. The proposed mechanism is cimetidine inhibition of chloroquine metabolism via hepatic microsomal enzymes. In five healthy volunteers, administration of a single 600 mg dose of chloroquine base in combination with cimetidine (400 mg at bedtime for four days) resulted in a 53% decrease in the apparent oral clearance of chloroquine, a 49% increase in its elimination half-life, and a 57% increase in apparent volume of distribution compared to five healthy volunteers given chloroquine alone. There was also a 47% reduction in systemic exposure to the major metabolite, monodesethylchloroquine, in cimetidine-treated subjects relative to controls. Another study performed by the same group of investigators found no significant interaction with ranitidine.

MANAGEMENT: Concomitant use of chloroquine and cimetidine should be avoided. Other H2-receptor antagonists such as famotidine, nizatidine, and ranitidine may be considered during chloroquine treatment, since they are not known to interfere with cytochrome P450 isoenzymes to any significant extent. The same precaution may be applicable to hydroxychloroquine, although no data are available to support this recommendation.

Chloroquine

Generic Name: chloroquine

Brand name: Aralen Phosphate, Aralen Hydrochloride

Synonyms: n.a.

What is Chloroquine?

Tagamet HB

Generic Name: cimetidine

Brand name: Tagamet HB, Tagamet

Synonyms: n.a.

What is Tagamet HB?