Benzyl alcohol

Pregnancy Category B.

There are no adequate and well-controlled studies with topical benzyl alcohol in pregnant women. Reproduction studies conducted in rats and rabbits were negative. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.

No comparisons of animal exposure with human exposure are provided in this labeling due to the low systemic exposure noted in the clinical pharmacokinetic study which did not allow for the determination of human AUC values that could be used for this calculation.

Pregnant rats were dosed with benzyl alcohol via subcutaneous injection at 100, 250, and 500 mg/kg/day. No teratogenic effects were noted at any dose. Maternal toxicity and decreased fetal weight occurred at 500 mg/kg/day. When pregnant rabbits received subcutaneous injections of benzyl alcohol at 100, 250, and 400 mg/kg/day, there were no teratogenic effects in offspring at any dose. In rabbits, maternal toxicity occurred at the two higher doses and was associated with decreased fetal weight at the highest dose.

It is not known whether benzyl alcohol is excreted into human milk. Because some systemic absorption of topical benzyl alcohol may occur and because many drugs are excreted in human milk, caution should be exercised when ULESFIA Lotion is administered to a nursing woman.

Long-term studies in animals to evaluate carcinogenic potential of benzyl alcohol lotion have not been conducted. No evidence of carcinogenic activity was noted for benzyl alcohol in 2 year oral carcinogenicity studies in rats (doses up to 400 mg/kg benzyl alcohol) or mice (doses up to 200 mg/kg benzyl alcohol) conducted by the National Toxicology Program.

Benzyl alcohol has produced mixed results in genetic testing. Benzyl alcohol was negative in the Ames test with and without metabolic activation, sex-linked recessive lethal assay, and a replicative DNA synthesis assay (conducted in male rats). Negative results were obtained in the mouse lymphoma assay with metabolic activation, but a positive response was noted in the mouse lymphoma assay without metabolic activation at a concentration producing a high level of cellular toxicity. Benzyl alcohol was positive in the Chinese hamster ovary chromosomal aberration assay with metabolic activation.

No fertility studies have been conducted with benzyl alcohol.

Clinical Trials Experience

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.

The rates of adverse reactions below were derived from two randomized, multi-center, vehicle-controlled clinical trials and one open-label study in subjects with head lice infestation.

Skin, scalp, and ocular irritation were monitored in the clinical trials. All subjects were queried about the presence of skin and scalp symptoms; the results are presented in Table 2.

Table 2. Monitored Adverse Reactions – Application Site Symptoms:

The subset of subjects who did not have pruritus, erythema, edema or pyoderma of skin and scalp, or ocular irritation prior to treatment were assessed for these signs and symptoms after treatment; the results are presented in Table 3.

Table 3. Monitored Adverse Reactions – Pruritus, Erythema, Pyoderma and Ocular Irritation with Onset After Treatment:

Other less common reactions (less than 1% but more than 0.1%) were, in decreasing order of incidence: application site dryness, application site excoriation, paraesthesia, application site dermatitis, excoriation, thermal burn, dandruff, erythema, rash, and skin exfoliation.