THIOTHIXENE

Fetal Risk Summary

Thiothixene is structurally and pharmacologically related to trifluoperazine and chlorprothixene (see also Trifluoperazine). The drug is not teratogenic in mice, rats, rabbits, and monkeys (1,2 and 3).

In a surveillance study of Michigan Medicaid recipients involving 229,101 completed pregnancies conducted between 1985 and 1992, 38 newborns had been exposed to thiothixene during the 1st trimester (F. Rosa, personal communication, FDA, 1993). One (2.6%) major birth defect (two expected), a cardiovascular defect (0.5 expected), was observed. No anomalies were observed in five other categories of defects (oral clefts, spina bifida, polydactyly, limb-reduction defects, and hypospadias) for which specific data were available.

Breast Feeding Summary

No reports describing the use of thiothixene during lactation have been located. The molecular weight (about 444) is low enough, however, that excretion into breast milk should be expected. The effects on a nursing infant from exposure to the drug in milk are unknown.

References

1. Owaki Y, Momiyama H, Yokoi Y. Teratological studies on thiothixene in mice. (Japanese) Oyo Yakuri 1969;3:315–20. As cited in Shepard TH. Catalog of Teratogenic Agents. 6th ed. Baltimore, MD: Johns Hopkins University Press, 1989:618.
2. Owaki Y, Momiyama H, Yokoi Y. Teratological studies on thiothixene (Navane) in rabbits. (Japanese) Oyo Yakuri 1969;3:321–4. As cited in Shepard TH. Catalog of Teratogenic Agents. 6th ed. Baltimore, MD: Johns Hopkins University Press, 1989;618.
3. Product information. Navane. Pfizer, 2000.