Terconazole

Teratogenic Effects

Pregnancy Category C.

There was no evidence of teratogenicity when terconazole was administered orally up to 40 mg/kg/day (25× the recommended intravaginal human dose of the suppository formulation) in rats, or 20 mg/kg/day in rabbits, or subcutaneously up to 20 mg/kg/day in rats.

Dosages at or below 10 mg/kg/day produced no embryotoxicity; however, there was a delay in fetal ossification at 10 mg/kg/day in rats. There was some evidence of embryotoxicity in rabbits and rats at 20 to 40 mg/kg. In rats, this was reflected as a decrease in litter size and number of viable young and reduced fetal weight. There was also delay in ossification and an increased incidence of skeletal variants.

The no-effect dose of 10 mg/kg/day resulted in a mean peak plasma level of terconazole in pregnant rats of 0.176 mcg/mL which exceeds by 17 times the mean peak plasma level (0.010 mcg/mL) seen in normal subjects after intravaginal administration of terconazole 80 mg vaginal suppository. This safety assessment does not account for possible exposure of the fetus through direct transfer to terconazole from the irritated vagina by diffusion across amniotic membranes.

Since terconazole is absorbed from the human vagina, it should not be used in the first trimester of pregnancy unless the physician considers it essential to the welfare of the patient.

Terconazole may be used during the second and third trimester if the potential benefit outweighs the possible risks to the fetus.

It is not known whether this drug is excreted in human milk. Animal studies have shown that rat offspring exposed via the milk of treated (40 mg/kg/orally) dams showed decreased survival during the first few post-partum days, but overall pup weight and weight gain were comparable to or greater than controls throughout lactation. Because many drugs are excreted in human milk, and because of the potential for adverse reaction in nursing infants from terconazole, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Carcinogenesis

Studies to determine the carcinogenic potential of terconazole have not been performed.

Mutagenicity

Terconazole was not mutagenic when tested in vitro for induction of microbial point mutations (Ames test), or for inducing cellular transformation, or in vivo for chromosome breaks (micronucleus test) or dominant lethal mutations in mouse germ cells.

Impairment of Fertility

No impairment of fertility occurred when female rats were administered terconazole orally up to 40 mg/kg/day for a three month period.

Adverse Reactions from Clinical Trials

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

Vaginal suppository

During controlled clinical studies conducted in the United States, 284 patients with vulvovaginal candidiasis were treated with terconazole 80 mg vaginal suppositories. Based on comparative analyses with placebo (295 patients), the adverse experiences considered adverse reactions most likely related to terconazole 80 mg vaginal suppositories were headache (30.3% vs. 20.7% with placebo) and pain of the female genitalia (4.2% vs. 0.7% with placebo). Adverse reactions that have also been reported but were not statistically significantly different from placebo were burning (15.2% vs. 11.2% with placebo) and body pain (3.9% vs. 1.7% with placebo). Fever (2.8% vs. 1.4% with placebo) and chills (1.8% vs. 0.7% with placebo) have also been reported. The adverse drug experience on terconazole most frequently causing discontinuation was burning (2.5% vs. 1.4% with placebo) and pruritus (1.8% vs. 1.4% with placebo).

Vaginal cream

During controlled clinical studies conducted in the United States, 521 patients with vulvovaginal candidiasis were treated with terconazole 0.4% vaginal cream. Based on comparative analyses with placebo, the adverse experiences considered most likely related to terconazole 0.4% vaginal cream were headache (26% vs. 17% with placebo) and body pain (2.1% vs. 0% with placebo). Fever (1.7% vs. 0.5% with placebo) and chills (0.4% vs. 0.0% with placebo), vulvovaginal burning, itching and irritation have also been reported. The adverse drug experience on terconazole most frequently causing discontinuation was vulvovaginal itching.

Post-marketing Experience

The following adverse drug reactions have been first identified during post-marketing experience with terconazole. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

General: Asthenia, Influenza-Like Illness consisting of multiple listed reactions including fever and chills, nausea, vomiting, myalgia, arthralgia, malaise

Immune: Hypersensitivity, Anaphylaxis, Face Edema

Nervous: Dizziness

Respiratory: Bronchospasm

Skin: Rash, Toxic Epidermal Necrolysis, Urticaria