ADVERSE REACTIONS In a controlled clinical trial, safety data from 141 patients who used metronidazole topical lotion (n=71), or the lotion vehicle (n=70), twice daily and experienced a local cutaneous adverse event which may or may not have been related to the treatments include: local allergic reaction, metronidazole topical lotion 2 (3%), lotion vehicle 0; contact dermatitis, metronidazole topical lotion 2 (3%), lotion vehicle 1 (1%); pruritus, metronidazole topical lotion 1 (1%), lotion vehicle 0; skin discomfort (burning and stinging), metronidazole topical lotion 1 (1%), lotion vehicle 2 (3%); erythema, metronidazole topical lotion 4 (6%), lotion vehicle 0; dry skin, metronidazole topical lotion 0, lotion vehicle 1 (1%); and worsening of rosacea, metronidazole topical lotion 1 (1%), and lotion vehicle 7 (10%). The following additional adverse experiences have been reported with the topical use of metronidazole: skin irritation, transient redness, metallic taste, tingling or numbness of extremities, and nausea.