i didn't realize how much marijuana was medically usable
According to an approved statement from the US Department of Justice in 1988, "Nearly all medicines have toxic, potentially lethal effects. But marijuana is not such a substance. There is no record in the extensive medical literature describing a proven, documented cannabis-induced fatality. In practical terms, marijuana cannot induce a lethal response as a result of drug-related toxicity."
From January 1997 to June 2005, the FDA reported zero deaths caused by the primary use of marijuana. Through that time period, 279 deaths were reported where marijuana was a possible "concomitant" drug used in conjunction with other drugs at the time of death. In contrast, common FDA-approved drugs which are often prescribed in lieu of marijuana (such as anti-emetics and anti-psychotics), were the primary cause of 10,008 deaths.
The study reported that smoking both tobacco and marijuana synergistically increased the risk of respiratory symptoms and COPD. Smoking only marijuana, however, was not associated with an increased risk of respiratory symptoms of COPD. In a related commentary, pulmonary researcher Donald Tashkin wrote, "...we can be close to concluding that marijuana smoking by itself does not lead to COPD".
Research done by the Scripps Research Institute in California shows that the active ingredient in marijuana, THC, prevents the formation of deposits in the brain associated with Alzheimer's disease. THC was found to prevent an enzyme called acetylcholinesterase from accelerating the formation of "Alzheimer plaques" in the brain more effectively than commercially marketed drugs. THC is also more effective at blocking clumps of protein that can inhibit memory and cognition in Alzheimer’s patients, as reported in Molecular Pharmaceutics.
A study by Complutense University of Madrid found the chemicals in marijuana promotes the death of brain cancer cells by essentially helping them feed upon themselves in a process called autophagy. The research team discovered that cannabinoids such as THC had anticancer effects in mice with human brain cancer cells and in people with brain tumors. When mice with the human brain cancer cells received the THC, the tumor shrank. Using electron microscopes to analyze brain tissue taken both before and after a 26- to 30-day THC treatment regimen, the researchers found that THC eliminated cancer cells while leaving healthy cells intact. The patients did not have any toxic effects from the treatment; previous studies of THC for the treatment of cancer have also found the therapy to be well tolerated. However, the mechanisms which promote THC's tumor cell–killing action are unknown.