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Isoniazid / pyrazinamide / rifampin Pregnancy and Breastfeeding Warnings

Isoniazid / pyrazinamide / rifampin is also known as: Rifater

Isoniazid / pyrazinamide / rifampin Pregnancy Warnings

Animal studies have not been reported with isoniazid/pyrazinamide/rifampin. Isoniazid animal studies have revealed evidence of embryolethality in rats and rabbits. Animal studies have not been reported with pyrazinamide. Rifampin animal studies have revealed evidence of embryotoxicity and teratogenicity. Congenital malformations (mainly spina bifida) were increased in the offspring of rats given rifampin during organogenesis at oral doses about 1 to 2 times the maximum recommended human dose (based on body surface area comparisons). Cleft palate was increased in fetuses of mice given oral rifampin about 0.2 to 0.8 times the maximum recommended human dose (based on body surface area comparisons). Imperfect osteogenesis and embryotoxicity were reported in rabbits given oral rifampin up to about 3 times the maximum recommended human dose (based on body surface area comparisons). There are no controlled data in human pregnancy. Isoniazid and rifampin have been reported to cross the placental barrier and rifampin has appeared in cord blood. Postnatal hemorrhages in the mother and infant have been associated with the use of rifampin during the last few weeks of pregnancy; administration of vitamin K may be indicated. FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

FDA pregnancy category: C Potential benefit should outweigh the potential risk.

Isoniazid / pyrazinamide / rifampin Breastfeeding Warnings

Isoniazid, pyrazinamide, and rifampin are excreted into human milk. The effects in the nursing infant are unknown. The manufacturer recommends that due to the potential for serious adverse reactions in nursing infants, a decision should be made to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

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