One rare side effect is cyclical vomiting syndrome. The phenomenon happens when a heavy, chronic user is affected by vomiting and severe abdominal pain, but they continue to use cannabis for short term relief, which ironically leads to more bouts. Typically, a user when then need invasive medical treatment to break the cycle.
In other rare cases, heavy cannabis users can develop a resistance to prescription drugs and anesthetics. At the very least, these users need higher doses of prescription medications over a longer period in order to achieve the same effects as non or moderate cannabis users, sometimes up to 2-4 times higher.
Sexual dysfunction is another potential rare side effect in heavy cannabis users. The American Journal of Men’s Health found that ED was twice as high in frequent weed users as it was in control groups.
Other reported conditions include lowered sperm counts, developing impaired vision and increased susceptibility to lung infections.
It is important to note that in all these cases, the side effects are reported in extreme, chronic cannabis users. Those that use moderately or infrequently have not reported any such side effects at all.
As cannabis research becomes less restricted and more mainstream, users will be able to rely on more unbiased, data-based information regarding the pros and cons of weed, risks, and benefits. Regardless, practicing moderation will always be the best way to go.
Sources: PubMed Central, Eat This Not That, American Journal of Men’s Health
