Of the 85 cannabinoids present in the resin of the marijuana plant, the two most abundant are THC (tetrahydrocannabinol) and CBD (cannabidiol). Since these substances come from the same plant and have the same chemical formula, it would be easy to assume that they have the same effect on the body. In reality, they produce very different effects on the user. Scientists continue to study their potential medical and therapeutic applications.
THC and CBD activate CB1 and CB2 receptors in the brain. THC more strongly activates CB1 receptors (most abundant in the brain) and causes psychoactive symptoms such as slowed reaction times, impaired memory and judgment, anxiety, and the euphoric “high” that can become addictive. In one 2012 study, subjects who were given THC versus CBD had more psychotic symptoms (paranoia, delusions) when faced with everyday situations versus abnormal ones. On the other hand, those given CBD experienced increased response times to abnormal situations, which could indicate CBD works with the natural instinct to recognize and react to potential danger.
Besides the key difference in psycho-activity, THC and CBD also affect the user differently in other ways that influence the medical applications they’re used for, or could be used for in the future.
THC Effects & Potential Applications
In spite of THC’s psychotic effects, it has useful medical applications. THC imitates some of the positive effects of a natural neurotransmitter known as anandamide which helps the body regulate sleep, appetite and pain perception. Because it causes the user to feel physically relaxed, tired and hungry, it may counteract the side effects of insomnia and loss of appetite caused by chemotherapy treatments and AIDS symptoms. Additional uses being studied for THC include treatment of glaucoma, spinal injuries, and MS. It has also being investigated for nerve regeneration, which could lead to even more applications.
CBD Effects & Potential Applications
Many of CBD’s effects on the user are the exact opposites of THC. For instance, instead of increasing fatigue, CBD actually promotes wakefulness among its users. Not only does CBD fail to produce a psychoactive reaction in its users it may have antipsychotic effects. Instead of creating anxiety, CBD decreases anxiety and paranoia in animal models. Studies also show that it can counteract the negative psychoactive effects of THC. For these reasons, CBD may be more useful for medical applications. It’s anti-inflammatory, antioxidant, and neuroprotective effects may be useful in treating MS, childhood epilepsy and similar conditions. Continued research suggests that CBD could also protect nerves from damage caused by strokes and other conditions.
Further medical research is important in providing more insight into the effects of these two powerful and seemingly opposite cannabinoids, especially since laboratory studies and small clinical studies suggest medical uses for THC and CBD.
References And Resources
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