Chlorhexidine is increasingly being used not only as an antiseptic to prevent hospital infections and an adjuvant in oral hygiene but also as a preservative in personal care products. As exposure to the agent becomes more widespread, reports of adverse reactions to it are increasing. Complications range from mild irritant contact dermatitis to life-threatening anaphylaxis. Allergic contact dermatitis in some cases precedes anaphylaxis. It is imperative that physicians be aware of the many possible sources of contact with this antiseptic and be alert to recognize the potentially debilitating and catastrophic reactions that may occur because of chlorhexidine sensitization.