May cause rebound congestion if used for >3 days. Not to be used by patients who have heart disease, high BP, thyroid disease, diabetes, or difficulty in urination due to enlargement of prostate gland. Use of product by > 1 person may spread infection. Patients w/ HTN or signs of reduced placental perfusion. Frequent or prolonged use of high doses may reduce placental perfusion. Pregnancy. Do not use during breast feeding. Not recommended for use in childn <6 yr.