Dosage is the key factor in achieving the most benefits and least adverse effects of cannabis. After following thousands of patients using medical cannabis for eight years, I’ve observed that dosing cannabis is unlike any therapeutic agent to which I was exposed in my medical training. A basic understanding of the key characteristics of cannabis dosing can empower you to make the most of this incredibly versatile, safe, and effective herb.
Some patients effectively use tiny amounts of cannabis, while others use incredibly high doses. I’ve seen adult patients achieve therapeutic effects at 1 mg of total cannabinoids daily, while others consume over 2,000 mg daily without adverse effects. And while a 2000-fold dosing range is unusual for a medication, researchers have failed to kill monkeys at doses even 300 times higher than the highest dose I’ve observed in the clinic.
Multiphasic Dose-Response Relationships
Within this unusually broad dosing range, cannabis exhibits an unusual relationship between the dose and the expected response. For most medications, a higher dose will result in a stronger therapeutic effect and a higher likelihood of adverse effects; this is described as a monophasic dose-response relationship. Cannabis simply does not follow this pattern.
For most cannabis consumers, gradually increasing their dose will at first result in stronger effects; but after a certain point (unique to each individual), subsequent dosage increases can result in weaker and weaker therapeutic effects, accompanied by an increase in unwanted effects.
Consumers who continue to increase their dosage to very high levels can often reclaim some or all of the previously lost benefit, and sometimes find additional therapeutic effects not achieved at the lower doses. Of course, ultra-high doses are much more expensive and usually produce more unwanted side effects. Most patients do much better at the lowest effective dose.
For many cannabis users, this means that less can be more. In a study of 263 opioid-treated cancer patients with poorly controlled pain, the group receiving 21 mg of combined THC and CBD each day experienced significant improvements in pain levels, more so than the group that received 52 mg daily. The group that received 83 mg daily reduced their pain no better than placebo, but experienced more adverse effects.
How is this possible? The endocannabinoid system is a sensitive, highly tuned physiologic infrastructure designed to maintain balance at a cellular level. When the cannabinoid receptors become overstimulated by high doses of cannabis, the cells pull the receptors inside, where they are either recycled or degraded. As cannabinoid receptor levels diminish, the effects of cannabis will diminish as well, even (or especially) in the face of dose escalation. This is known as “tolerance-building,” something that many regular cannabis users have experienced.
The term “therapeutic window” describes the range between the lowest effective dose and the dose that produces unwanted or intolerable side effects. People who have little or no experience using cannabis typically have a very narrow therapeutic window, while regular users develop a wider therapeutic window. This is due to the fact that individuals build tolerance to the various effects of cannabis at different rates, and most build tolerance to the unwanted effects faster than the desired effects.