Sinarest Drops contain two active ingredients, Phenylephrine and Chlorpheniramine. Phenylephrine is a decongestant that works by narrowing blood vessels in the nasal passages to reduce congestion. Chlorpheniramine is an antihistamine that blocks the action of histamine, a substance in the body that causes allergic symptoms. Together, these ingredients help relieve symptoms such as nasal congestion, runny nose, sneezing, and itchy/watery eyes. Sinarest Drops are commonly used to treat symptoms of the common cold, flu, allergies, and other respiratory illnesses. It is important to follow the dosage instructions provided by your healthcare provider or on the product label to ensure safe and effective use of Sinarest Drops.