Sinudrin Oral Drops contain Phenylpropanolamine (6.25mg per ml) and are used to relieve nasal congestion caused by colds, allergies, or sinus infections. As a decongestant, it works by constricting the blood vessels in the nasal passages, which reduces swelling and facilitates easier breathing. These oral drops come in a 15ml bottle. Always follow the recommended dosage instructions and consult a healthcare provider before use.