Cold combination medicines like Robitussin Severe Multi-Symptom Cough Cold + Flu and Severe Multi-Symptom Cough Cold + Flu Nighttime provide relief for your symptoms. Here's how they work: Decongestants shrink blood vessels in the lining of the nose. As a result, less blood is able to flow through the nasal area, and swollen tissue inside the nose gets smaller. Found in products such as: Robitussin Severe Multi-Symptom Cough Cold + Flu and Robitussin Severe Multi-Symptom Cough Cold + Flu Nighttime. Robitussin Severe Multi-Symptom Cough Cold + Flu Nighttime and Children’s Robitussin Nighttime Cough Long-Acting DM. Cough suppressants control your cough: Some block the cough reflex (antitussives), while expectorants thin mucus in the lungs to help clear airways and make coughs more productive (expectorants). Found in products such as: Robitussin Severe Multi-Symptom Cough Cold + Flu and Robitussin Maximum Strength Cough + Chest Congestion DM. Analgesics, like acetaminophen, temporarily reduce fever and provide relief from aches and pains associated with colds, like headaches or body aches. Found in products such as: Robitussin Severe Multi-Symptom Cough Cold + Flu and Robitussin Severe Multi-Symptom Cough Cold + Flu Nighttime.