- all cough medicines (cough linctuses) are available over the counter, except for controlled drugs.
- there are two types of over the counter (OTC) cough medicine:
- cough expectorant
- cough suppressant - decrease cough reflex to normal levels, most common OTC suppressant is dextromethorphan
- although there is little evidence that either is effective (1).
- the logic behind use is that:
- a 'dry cough' with little phlegm requires a cough suppressant e.g. codeine and pholcodeine linctus.
- a 'productive cough' requires a cough expectorant to help bring up phlegm e.g. 'ammonia and ipecacuanha mixture BPC' - expectorants are designed to force the cough reflex to propel the phlegm out of the bronchi - there is no evidence that they have any effect.
- opiate antitussives (codeine or pholcodine) are not recommended since it has no greater efficacy than dextromethorphan and the side effects are much greater