Coricidin is not a decongestant, but a name-brand medication containing the antihistamine 'chlorpheniramine,' states Drugs.com. Antihistamines may be taken at the onset of symptoms, prior to exposure to symptom triggers or daily to help keep symptoms under control, says the National Library of Medicine.
Coricidin is marketed as Coricidin HBP and contains acetaminophen -a pain and fever reducer- in addition to the antihistamine. Various medicines are available for treating colds, allergies, chest congestion and flu-like symptoms. Coricidin HBP does not contain decongestants, as they may cause an increase in blood pressure or interfere with the effectiveness of high blood pressure medication, reports the American Heart Association.