Zinc, a common essential mineral found in foods, also has a number of medicinal applications. You may use zinc oxide paste to treat diaper rash or for other skin ailments. Some lozenges used to treat cold symptom also contain zinc. You can develop an allergy to zinc and it can also cause a number of side effects unrelated to an allergic reaction.
A Tunisian study reported in the October 2010 issue of "Acta Diabetologica" reported a case of allergic reaction in a diabetic recently switched to insulin from oral anti-diabetics. Skin testing revealed a zinc allergy. Researchers from the University of Pennsylvania School of Dental Medicine reported a case of zinc allergy in the October 2007 issue of the "International Endodontic Journal." The patient, who had a confirmed zinc oxide allergy, underwent a successful root canal surgery using zinc-free dental materials. Dental cement often contains zinc phosphate.
Symptoms of zinc allergy may depend on what type of product you used. Ointments may cause localized skin reactions such as itching, blistering, burning, stinging, redness and swelling. Oral zinc may cause more systemic reactions such as rash, hives, swelling, dry mouth, shortness of breath, chest tightness, watery eyes, runny nose or collapse.
If you have a zinc allergy, avoid supplements, ointments, eye drops, dental adhesives, nasal sprays and lozenges that contain zinc. Food high in zinc include oysters and meats. Ask your doctor about food restrictions if you have a zinc allergy.
When you have a reaction to a substance, you may first assume you have an allergy to it. But zinc can cause reactions that have nothing to do with allergies. For example, nasal spray containing zinc can cause a loss of your sense of smell, MedlinePlus warns, so do not use these nasal sprays. Zinc can also cause nausea, vomiting, a metallic taste in your mouth, mouth irritation or diarrhea.