Medicinal cannabis is any pharmaceutical-grade medicine derived from the Cannabis Sativa plant used to treat or relieve a symptom, ailment or condition. Pharmaceutical-grade medicines must contain raw materials sourced from licensed manufacturers compliant to Therapeutic Goods Order No. 93 (Standard for Medicinal Cannabis/TGO 93). TGO93 is a therapeutic goods standard developed by the TGA that specifies minimum quality requirements for medicinal cannabis products, and ensure sources are rigorously tested for contaminants like bacteria, fungi, pesticides and heavy metals, and standardised for active constituents.
Phytocannabinoids and other active constituents in medicinal cannabis
Whilst there are more than 100 different phytocannabinoids found in cannabis plants, the principle and most widely studied for their potential benefits in humans are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). In spite of structural variances between the phytocannabinoids and the endogenous cannabinoids, similar interactions have been observed within the endocannabinoid system owing to their medicinal properties. Cannabis contains over 400 different chemical constituents including a class of volatile compounds known as terpenes. Classically attributed to providing the characteristic flavor and fragrance of cannabis, the primary terpenes in cannabis are also reported to influence either the pharmacodynamics or pharmacokinetics of CBD and THC producing what is known as the “entourage effect”. It is reported that their inclusion in medicinal cannabis preparations may enhance the overall benefits of the primary phytocannabinoids.
There are many studies reporting on the therapeutic effects of medicinal cannabis, and we will cover some of the key benefits here. However, evidence is continually emerging for further potential applications. What is evident is that cannabinoids may provide broad benefits across several health conditions, either with symptom management, disease progression or quality of life. As a legal treatment, medicinal cannabis where appropriate may form part of a multi-therapy approach or as a further option to other medications where their effects have been limited.
TGA Therapeutic Guidelines
There is generally more information in the medical literature on the adverse reactions associated with the use of non-medicinal cannabis than there is with therapeutic or medicinal cannabis. The available information about medicinal cannabis is predominantly on the short-term adverse effects.
There is limited evidence about the health risks of long-term medical use of cannabinoids, but in general those reported are similar to those reported for short-term use. Some of the harms reported among long-term users of recreational cannabis could possibly apply to the long-term medical use of cannabis and cannabinoids, but more research is needed to draw evidence-based conclusions.
Addiction is unlikely with cannabis used as a medicine. The recommended dose is usually lower than that for recreational use. You should take particular care, however, if you have been addicted in the past. High dosages of medicinal cannabis taken over a longer period may lead to addiction. Quitting may then cause withdrawal symptoms, such as mild forms of restlessness, irritability, insomnia and nausea.
Your doctor will determine, in consultation with you:
You will probably start with a low dosage. If the effect is insufficient, your doctor will gradually increase the dosage. No maximum dose has been determined. Your doctor can keep increasing the amounts of cannabis you take until an effective result is achieved and stop when you start feeling side effects.
There are numerous pathways under the Therapeutic Goods Regulation 1990 that allow unregistered therapeutic goods (exempt from being registered) to be supplied in Australia. Cannabinoids are now (2016) listed as therapeutic goods in the Poisons Standard (either schedule 4 or schedule 8). Cannabinoids are now treated like any other drug.