There have been several cases of people using<unk>  nasal sprays and suffering a loss of sense of smell. In 2009 the US Food and Drug Administration issued a warning that people should not use nasal sprays containing<unk> . Excessive<unk>  intake may result in an unpleasant taste and/or nausea.
Zinc and the common cold
Vitamin C and the common cold
Vitamin D and respiratory tract infections
Lewis lead
MMR vaccine and autism
Breastfeeding and HIV
Alcohol and cancer
Alcohol and cardiovascular disease