No. 1 pharmacist recommended. Non-drowsy. Clinically proven to reduce the duration of the common cold. Zinc, Gluconate, Glycine. Take at the first sign of a cold. Great tasting flavor! Homeopathic. No artificial colors or preservatives. Effectiveness: Cold-Eeze, the original Zinc Gluconate Glycine formula, shown to be safe and effective in reducing the severity of symptoms by 42% and duration by 3 to 4 days in two double blind placebo controlled clinical studies. This product has no expiration date.