A cough medicine or antitussive is a medication given to people to help them stop coughing.
The type of cough medication taken depends on the nature of the cough. Dry coughs are treated with cough suppressants (antitussives) that suppress the body's urge to cough.
Productive coughs (coughs associated with phlegm) are treated with expectorants, drugs designed to loosen and help the body expel mucus from the respiratory tract.
Cough suppressants can act centrally (on the brain) or locally (on the respiratory tract) to suppress the cough reflex.
Centrally acting suppressants include DXM (dextromethorphan), noscapine, ethyl morphine, and codeine.
Peripherally acting substances include local anaesthetics that reduce sensation of the nerves of the throat, and demulcents that coat the back of the throat.
One might think that it is unwise to suppress the cough reflex, and with that the possibility of expelling mucus from the respiratory tract. However, severe coughing can actually lead to lung irritation, which starts a vicious circle. Above that, the cough reflex is very strong and will not be completely suppressed.
An expectorant is a medicine or herb which increases the expulsion of tracheal or bronchial mucus through expectoration or coughing.
Aniseed (Pimpinella anisum), Balm of Gilead (Populus gileadensis), Balsam of Peru (Myroxylon perierae), Balsam of Tolu (Myroxylon toluifera), Blood Root (Sanguinaria canadensis), Coltsfoot (Tussilago farfara), Comfrey (Symphytum officinale), Elder Flower (Sambucus nigra), Elecampane (Inula helenium), Garlic (Allium sativum), Golden Seal (Hydrastis canadensis), Grindelia (Grindelia camporum), Hyssop (Hyssopus officinalis), Iceland Moss (Cetraria islandica), Irish Moss (Chondrus crispus), Liquorice (Glycyrrhiza glabra), Lobelia (Lobelia inflata), Lungwort (Sticta pulmonaria), Marshmallow (Althaea officinalis), Mouse Ear (Hieracium pilosella), Mullein (Verbascum thapsus), Pleurisy Root (Asclepias tuberosa), Senega (Polygala senega), Skunk Cabbage (Symplocarpus foetidus), Squill (Urginea maritima), Thuja (Thuja occidentalis), Thyme (Thymus vulgaris), Vervain (Verbena officinalis), White Horehound (Marrubium vulgare), Wild Cherry (Prunus serotona).
In 2002, researchers at the University of Bristol (Schroeder & Fahey) published a study in the British Medical Journal indicating that some cough medicines are no more effective than placebos.
- Schroeder K, Fahey T. Systematic review of randomised controlled trials of over the counter cough medicines for acute cough in adults. BMJ 2002;324:329-31. Fulltext (http://bmj.bmjjournals.com/cgi/content/full/324/7333/329). PMID 11834560.
- DXM Harm Reduction Project (http://www.dextromethorphan.ws/)