Why Medical Cannabis is Less Imparing and Safer than Alternatives

Many ask why would someone use medical cannabis for various conditions like muscle spasms, pain, or anxiety when there are many other medications currently available for those conditions? This question arises due to its controversial nature and its illegality until recent history for medical use.

            Although many medications such as opiates, muscle relaxants, and anti-anxiety agents are used for treating some conditions, these medications usually require progressively escalating doses and, they are only effective when they are also acutely impairing. Most medications’ period of effectiveness is  linked to metabolism. So when you take a medication, it is effective for a time after absorption until the body metabolizes them to inactive chemicals that are then excreted by the body.

            Medical cannabis, on the other hand, does not require constantly escalating doses in order to maintain efficacy. It has been shown that tolerance does not develop for many of the modes of action that cannabis treats, including pain. It has been shown that a pain dose can remain stable without tolerance reducing its efficacy for at least a year.  In addition, medical cannabis is very slowly metabolized by the body. This means that the wearing off of its acute effects (which can include mild impairment), is not due to metabolism, but is instead due to “redistribution.” Redistribution is a pharmacokinetic term that refers to a drug concentrating in one area of the body initially (the brain in this case) then migrating or redistributing to another (for cannabis, to the body fat).

Inhaled medical cannabis concentrates rapidly in the brain- because cannabis is very fat soluble and the brain is basically a big pile of fat-  beginning to work in seconds and peaking within 10-15 minutes. The acute phase (that is the time frame under which it can be impairing) typically lasts between 30 to 60 minutes, with extreme cases ranging up to 120 minutes. However, once a patient is regularly dosed in a medical manner, this impairment phase is dramatically reduced because tolerance rapidly reduces the drowsiness and impairment that is initially present. Medical cannabis, because it is so slowly metabolized, however, remains effective for many hours after dosing. This is because it is released by the fat cells at a slow rate but that is at a level that does not cause acute impairment. This is why you can have a regular inhaled dose once or twice daily and it can still reduce pain, anxiety, muscle spasticity for long periods of time after dosing.

This is a major difference from most other medications which are only effective while they are acutely impairing and become less effective as the body metabolizes them to inactive forms. It is also why medical cannabis is arguably safer, in terms of impairment, because it is metabolized very slowly and retains its effectiveness long after the acute impairment phase is long gone. From a pharmacokinetic viewpoint, this means that medical cannabis may be a much more useful and safer medication for pain, muscle spasticity, and anxiety as compared to currently available alternatives.

This pharmacokinetic  profile and lack of tolerance-based escalation make cannabis an incredibly useful medication. More importantly, because there are no cannabinoid receptors in the brain stem (where the body’s breathing reflex resides) means that there is no lethal dosage for cannabis- unlike the opioids, benzodiazepines, and muscle relaxants which kill tens of thousands annually due to accidental overdoses. With more research and clinical trials in support of its usage, it is likely that medical cannabis will be the preferred treatment for many chronic conditions because its liability to cause death and impairment is much lower than any available pharmacologic alternatives.


Ethan Carruthers