Cannabis contains over 60 chemical compounds, of which THC and CBD are the most prolific and are the only two to have been well characterized to date. Many strains of cannabis are known for having ample amounts of THC while high-CBD strains are less common; however as research continues the medical community has been paying more attention to the therapeutic effects of Cannabidioil (CBD).
Both THC and CBD have important health benefits. THC has antispasmodic, analgesic, anti-tremor, anti-inflammmatory, appetite stimulating and anti-emetic properties while CBD has anti-inflammatory, anticonvulsant, antipsychotic, antioxidant, neuroprotective and immunomodulatory effects.
Clinical use of THC is often limited due to it's often times unwanted psychoactive side effects. It is for this reason that interest in non-psychoactive phytocannabinoids such as CBD have substantially increased recently. In a more recent practices CBD is being used to reduce the psychoactive effects of THC such as memory impairment and paranoia.
CBD appears to conteract the sleep-induicing effects of THC. This is what now makes cannabidioil such an appealing chemical to the medical community as it helps negate the intoxicating effects of tetrahydrocannabinol (THC) which has been a large barrier as far as acceptance of medical cannabis. While it has been known to cause paranoia and anxiety in some individuals, CBD works to counteract those side effects. It is because of this that CBD benefits extend to use in clinical trials on young children with epilepsy.
Another rather large difference between the two chemical compounds is that high THC cannabis is commonly used for sleep while CBD seems to promote alert, awakefulness.
The legality of each stands in stark contrast, with items containing more than 0.3% THC being recognized as federally illegal Schedule 1 narcotics while CBD is recognized as a dietary supplement since 2014. One that is legal to own but illegal to grow. The legal status(es) of these two items are changing regularly on local/state levels while the federal government has long held firm.