Runny nose—also known as rhinorrhea—refers to the production of excess nasal fluid caused by conditions like allergies and the common cold. There are many medications for treating runny nose, most of which can be purchased at your local grocery store or pharmacy.

Antihistamines are medications that inhibit the effects of histamine, a chemical that causes allergy symptoms like runny nose and sneezing. According to Merck.com, antihistamines have anticholinergic effects that help dry out mucus membranes, thereby reducing nasal secretions. Diphenhydramine, cetirizine and loratadine are among the many over-the-counter antihistamines available today.

While more frequently recommended for nasal congestion, decongestants can also help reduce nasal inflammation associated with rhinorrhea. Decongestants like pseudoephedrine and phenylephrine are included in many over-the-counter allergy medications.

Sprays containing vasoconstricting drugs like propylhexedrine or levomethamphetamine can help shrink blood vessels in the nose, leading to a reduction in rhinorrhea and other allergy symptoms. Corticosteroid nasal sprays such as mometasone and fluticasone are available by prescription and may be useful for more persistent cases of runny nose.

Avoiding situations that cause nasal irritation can help prevent runny nose. According to MayoClinic.com, irritants like cigarette smoke and chemical cleaning products can trigger runny nose in sensitive individuals, as can exposure to allergens like dust mites, pollen and certain food proteins.

Rarely, runny nose can signal a more serious condition. Seek medical attention if you experience runny nose accompanied by green, yellow or bloody mucus or for symptoms lasting longer than 10 days.