We thank Mr Andrew da Roza and Dr Quek Koh Choon for their letters (Cannabis reclassification: Separate health policies from science of medicinal drugs; and Make a stand on not allowing any narcotics to be 'legalised', both Dec 7).

Singapore has a framework for the supply, prescription and dispensation of controlled drugs for medical purposes. This includes applications for the use of pharmaceutical products containing cannabinoids, which are reviewed by the Central Narcotics Bureau, Health Sciences Authority (HSA), Ministry of Health and Ministry of Home Affairs.

Like other therapeutic products, cannabinoid pharmaceuticals need to undergo rigorous scientific review by HSA before they can be registered for use. Manufacturers are required to substantiate the safety, quality and efficacy of the pharmaceuticals. Following registration, the drugs can be prescribed by a Singapore-registered doctor for use, with proper documentation and in accordance with HSA's approved conditions.

To date, HSA has not received any application for the registration of cannabinoid pharmaceuticals.

It is important to differentiate between unprocessed or raw cannabis, and pharmaceutical products containing cannabinoids. There is no scientific evidence on the safety and efficacy of raw cannabis to treat medical conditions. On the contrary, consumption of cannabis has been found to be associated with irreversible brain damage, brain shrinkage and serious mental illnesses.

Hence, Singapore strongly disagrees with the decision made by the United Nations Commission on Narcotic Drugs (CND) to remove cannabis from the list of most dangerous drugs. The CND decision may send a wrong signal that cannabis is not as harmful as previously assessed, despite strong evidence showing otherwise. It could lead to increase in the abuse of cannabis, with serious adverse consequences to lives, families and communities.

As Dr Quek pointed out, Singapore has battled hard to control drug abuse in our society. We will not relax our zero-tolerance stance towards drugs, including cannabis. The international drug control conventions allow countries the flexibility to adopt national control measures that are stricter than those required by the conventions.

Cannabis is addictive and harmful. We are committed to working towards a drug-free society for Singaporeans, and will continue to enforce strictly against the trafficking, possession, consumption and import or export of cannabis and other illicit drugs.

Raymond Chua

Group Director, Health Regulation Group

Ministry of Health

Lu Xinyi

Director, Media Relations

Ministry of Home Affairs