The active ingredients in cannabis for medical use are cannabinoids, specifically THC (delta-9-tetrahydrocannabinol) and CBD (cannabidiol). THC is responsible for pain relief, anti-nausea, anti-emetic, relaxing, and appetite-stimulating effects. CBD enhances the pain-relieving properties of THC, prolongs its duration of action, and reduces side effects. CBD also has anti-convulsive, sedative, and anti-psychotic properties. Standardized and titrated medical marijuana contains THC and CBD.