What are the side effects of MMJ?

All medicines have side effects. Have you ever taken a look at the warning label inside of a Tylenol bottle? The list of side effects seems endless and a large number are very serious including itchiness, diarrhea, trouble breathing, severe dizziness, lower back pains, loss of appetite,  nausea, stomach pain & unusual bleeding .   With any medication, it is very important to understand the main side effects, how to recognize these side effects, and how to appropriately deal with these side effects. Medical marijuana is no exception. When obtaining your medical marijuana card, your medical marijuana doctor should make sure to always review the potential side effects of medicinal marijuana use. If your medical marijuana doctor did not appropriately discuss these side effects with you or you are simply interested in obtaining your medical cannabis card and want to know more about medicinal marijuana, this blog post will be very helpful as we will outline several of the major side effects as indicated by the most current research and the California medical association.

As outlined by the California medical association, multiple health risks have a documented association with medical cannabis use.


  1. Addiction: Addiction to cannabis may be characterized by escalating use, inability to cut back, craving, harmful consequences, and physical dependence. Epidemiologic data from a national comorbidity study indicate that about 9% of adult cannabis users become addicted and that this risk is substantially increased among individuals who begin using before age 18. Although of little consolation, among adults the incidence is low compared to alcohol use (15%), opioids (23%) or nicotine (32%).
  2. Short Term Cognitive Effects: Cannabis intoxication causes well-defined impairments in the following brain functions: Memory, sense of time, sensory perception, attention span, problem solving, verbal fluency, reaction time, and psychomotor control. The short term effects of cannabis last approximately 1-4 hours, depending on potency of the cannabis, the route of administration, and the tolerance of the user. There are no reported cases of death resulting from cannabis overdose.
  3. Long Term Cognitive Effects: The possible medicinal use of cannabinoids for chronic diseases emphasizes the need to understand the long term cognitive effects of these compounds. Results of a meta-analysis indicated that there might be decrements in the ability to learn and remember new information in chronic users, whereas other cognitive abilities were unaffected. The authors opined that, under the more limited conditions of exposure that would likely be seen in a medical setting, the benefits could outweigh problematic effects and the therapy might thereby prove to be acceptable.
  4. Adolescents and Young Adults: The evidence suggests that cannabis can adversely affect adolescents who initiate use early and young adults who become regular users. Compared to adults, adolescents and young adults may have greater vulnerability to the toxic effects of cannabis on the brain, especially when alcohol and cannabis are used together. In addition to increased risk of addiction, use of cannabis among adolescents is associated with poorer educational outcomes and occupational attainment. There is also the possibility that cannabis increases the risk of developing mental illness in this age group.
  5. Psychiatric Conditions: Cannabis intoxication can cause transient mood, anxiety, and psychotic symptoms. The relationship between cannabis use and long term risk of psychiatric disorders is less well understood. Cannabis use has been weakly correlated with long term risk of mood disorders and anxiety disorders. The association between cannabis use and psychotic disorders is more robust. Cannabis can unmask symptoms among individuals who have pre-existing vulnerability (such as a family history) to schizophrenia. Additionally, there is some evidence that cannabis may be an independent risk factor for the development of psychotic disorders such as schizophrenia. Although the mechanism is unknown, repeated studies have shown that cannabis use is correlated with an increase in the risk of manifesting schizophrenia, an illness that affects approximately 1% of the global population.
  6. Obstructive Lung Disease: Given the increased risk of chronic obstructive pulmonary disease (COPD) in tobacco smokers, there is concern that a similar risk may exist among smokers of cannabis. Cannabis smoking by itself probably does not lead to COPD but smoking both cannabis and tobacco is associated with a greater risk of COPD than smoking only tobacco.
  7. Lung Cancer: The constituents of cannabis smoke are quantitatively analogous to those of tobacco smoke, with the exceptions of delta-9-tetrahydrocannabinol (THC) – found only in cannabis – and nicotine – found only in tobacco. Paradoxically, epidemiologic findings are inconsistent with the biological plausibility of cannabis being carcinogenic in aerodigestive tissue. Using over 1,000 incident cancer cases and over 1,000 cancer-free controls matched to cases on age, gender, and neighborhood, investigators at UCLA found no positive associations for malignancies after adjusting for several confounders (including cigarette smoking). They concluded that the association of pharyngeal and pulmonary cancers with cannabis, even long-term or heavy use, is “not strong and may be below practically detectable limits.”
  8. Motor Vehicle Accidents: Epidemiological studies have been inconclusive regarding whether cannabis use causes an increased risk of accidents; in contrast, unanimity exists that alcohol use increases crash risk.xxiii In tests using driving simulation, neurocognitive impairment varies in a dose-related fashion, and are more pronounced with highly automatic driving functions than with more complex tasks that require conscious control, whereas alcohol produces an opposite pattern of impairment.xxiv Cannabis smokers tend to over estimate their impairment and compensate effectively while driving by utilizing a variety of behavioral strategies. During driving simulation, experimental subjects under the influence of cannabis drive slowly, leave a large distance between themselves and the car in front of their simulated car, and avoid changing lanes.
  9. Reproductive Risks: The compounds found in cannabis readily cross the placenta, where the growing fetus absorbs them, and pass into breast milk, where the nursing infant ingests them. Cannabis affects many aspects of reproductive physiology in both men and women, though the long term consequences of these effects remain unclear.xxv Cannabis use during pregnancy and early development has been correlated with low birth weight as well as developmental delay and behavioral problems including addiction, although the causal link to cannabis use has not yet been established.


While these side effects should be taken seriously, they should not be viewed as a reason not to obtain a medical marijuana card or try medical cannabis for the treatment of your medical condition. The only true contraindication to medicinal marijuana use is pregnancy and any woman of childbearing age who even thinks they might be pregnant should not use medical marijuana.

With the use of any medication, the side effects should always be weighed against the potential benefits. While this should be a discussion that each patient has with his/her medical marijuana doctor, this blog will hopefully give patients with a medical marijuana card, or those interested in obtaining one, a better understanding of some of the potential side effects of medicinal marijuana use.