Over the counter medication
June 2005
Further investigation required
As described, all newly marketed drugs are classified as a Prescription only medicine (POM). This means that while a new drug entity is still being monitored closely it is unlikely to be available OTC, and thus the third criterion for retaining POM status ‘further investigation required’ is less likely to apply to OTC medicines than the two previously discussed (the need for supervision because of issues of adverse events or diagnosis, and the potential for incorrect usage [misuse]). Once circumstances change however, new investigations might be required to confirm OTC safety, and hence appropriateness of OTC availability of a drug. This should mean that the product would revert to POM status for this period, as happened when suspicions of carcinogenicity were associated with the head lice treatment carbaryl (Anonymous 1995).