Another important finding is that marijuana can suppress testosterone secretion in men, which may result in decreased libido, impotence, and gynecomastia (N. Engl. J. Med. 1974;290:872). Many teens believe cannabis is safe because it’s a plant, and consequently, may not relate these symptoms to its use.
The research on cannabis smoke and its relationship to cancer are limited by inadequate sample sizes and confounding factors not taken into account, but there does seem to be a relationship between cannabis smoke and lung cancer and bladder cancer (J. Psychoactive Drugs 1994;26:285; Urology 2006;67:100). However, head and neck cancers have not shown a relationship to marijuana use (Cancer Epidemiol. Biomarkers Prev. 2009;18:1544-51). Cardiovascular effects have been related to the increased sympathetic activity and decreased parasympathetic activity that can result in bradycardia and hypotension with high doses. This may be of particular concern in older people with coronary artery disease (J. Clin. Pharmacol. 2002;42:58S).
The medicinal properties of marijuana are an important consideration. Marijuana has been shown to be particularly effective in controlling some forms of seizure, pain, nausea from chemotherapy, muscle spasms caused by multiple sclerosis, and Crohn’s disease. The FDA has approved tetrahydrocannabinol, or THC, a key ingredient in marijuana, to treat nausea and improve appetite. In states that have legalized cannabis, qualifying patients can get prescriptions from their physicians to use at authorized dispensaries. For some patients, the effects can be life changing; for others, it can help with pain management and the discomfort associated with certain illnesses.
Beyond the scope of medicine is the economics of the legalization of marijuana. States that have already legalized it have seen revenues in the billions. Marijuana cash crops are estimated at $14 billion in revenue. Jon Gettman’s 2007 study, “Lost Taxes and Other Costs of Marijuana,” states that the prohibition of marijuana costs the government $113 billion, while it costs taxpayers $31.1 billion each year. The study projects that legalization of cannabis may save the criminal justice system $10.7 billion and an additional $6.2 billion for taxpayers. That sort of money does talk: Regardless of current opposition to the legalization of marijuana, it is probably just a matter of time before marijuana is legalized in every state.
The scope of marijuana issues is broad and, for many, controversial. The drug can serve as a healer, create health challenges, lead to drug addiction, or even become a significant revenue source to a state’s coffers. As providers, we need to be able to provide our patients with research-based information and resources, and dispel myths, so that they can make informed decisions for themselves that are in the best interests of their children.
Dr. Pearce is a pediatrician in Frankfort, Ill. She had no relevant financial disclosures. E-mail her at pdnews@frontlinemedcom.com.
*Correction, 1/29/2015: An earlier version of this story had the incorrect date of publication of the AAP's policy statement.