A demulcent (derived from the Latin: demulcere "caress") is an agent that supposedly forms a soothing film over a mucous membrane, relieving minor pain and inflammation of the membrane. Demulcents are sometimes referred to as mucoprotective agents. Demulcents such as pectin, glycerin, honey, and syrup are common ingredients in cough mixtures and cough drops. Methylcellulose, propylene glycol and glycerine are synthetic demulcents.
- Mandel, I. D. (1987). "The Functions of Saliva". Journal of Dental Research. 66 (2 suppl): 623–627. doi:10.1177/00220345870660S203. ISSN 0022-0345.
- Frye, Rebecca, Justin Bailey, and Amy Blevins. "Which treatments provide the most relief for pharyngitis pain?." Clinical Inquiries, 2011 (MU) (2011).
- Rouhi, Hamid, and Forouzan Ganji. "Effect of Althaea officinalis on cough associated with ACE inhibitors." Pakistan Journal of Nutrition 6.3 (2007): 256-258.
- Boyd, Eldon M. (1952). "Cough medication and antihistaminic drugs.". Can Med Assoc J. 67 (4): 289–92. PMC . PMID 13009543.