The scientific and clinical evidence to support the medicinal use of cannabis and cannabis-derived products is not yet overwhelming. However, it is well-established enough to suggest cannabis has therapeutic benefits in treating people with serious conditions such as:
- chronic pain for which other pain relief treatments are ineffective, or have bad side-effects
- neurological disorders, including multiple sclerosis and motor neurone disease
- nausea and vomiting for which existing drugs are ineffective or have bad side-effects
- HIV-related and cancer-related wasting (cachexia).
Cannabis provides a ‘broad spectrum’ effect. For example, patients with HIV/AIDS-related conditions, cannabis can reduce nausea, pain and joint aches, while providing appetite stimulation and potentially reducing anxiety.
Medicinal cannabis is grown and prepared for pharmaceutical use.
Research continues into cannabis-derived medicines, such as sprays, tablets and also extraction methods including vaporisation, so that users can avoid the harmful effects of smoking cannabis.
Under New Zealand law, the Minister of Health has the power to authorise the medicinal use of cannabis products. There have been few applications however, and ministerial approval has been granted for only a small number of patients.