If the medicine becomes cloudy or unclear it should be discarded and replaced. Droppers and inhalators should not be shared with other people, and they should not be inserted into the nostril. The benefits of oral decongestants in treating sinusitis have not been confirmed by any studies. They may cause constriction of other vessels in the body, temporarily raising blood pressure in people with hypertension. Decongestant sprays and drops, too, are absorbed into the body and can sometimes cause these side effects.
Children appear to metabolize all types of decongestants differently from adults.
Decongestants should not be given to infants and small children. They are at particular risk for side effects that depress the central nervous system, which can result in changes in blood pressure, drowsiness, deep sleep, and, rarely, coma. Of some concern is a study indicating that decongestants, particularly those containing pseudoephedrine, may increase the risk for stroke in certain individuals. It is important to note, however, that this occurs very rarely. Those at risk are people whose blood vessels are highly susceptible to contraction, including those with migraines and Raynaud's phenomenon, which causes high sensitivity to cold.