An antifungal and antiseborrheic agent, used topically. Since the last update we have not found any published data on its excretion in breast milk. The small dose and low plasma uptake of most topical dermatological preparations make it unlikely that significant amounts will pass into breast milk. There is no cutaneous absorption of selenium sulphide through intact skin (Sánchez 1984), but there may be severe absorption and poisoning if applied to heavily abraded skin (Ransone 1961). Since it is highly irritating to mucous membranes and toxic if ingested, it should not be applied to the chest in order to prevent the infant from ingesting it; if necessary, apply after breastfeeding and clean well with water before the next feed. List of WHO essential medicines: compatible with breastfeeding (WHO / UNICEF 2002).