Delta-9-tetrahydrocannabinol
Delta-9-tetrahydrocannabinol, commonly known as THC, is the primary psychoactive compound found in the cannabis plant, Cannabis sativa. It has garnered attention for its potential medicinal applications, particularly in alleviating nausea and vomiting in cancer patients undergoing chemotherapy, as well as helping individuals with AIDS and multiple sclerosis manage weight loss. THC can be administered in various forms, including oral tablets (such as Marinol and Cesamet) and through smoking or ingestion of cannabis products like brownies or cookies.
The compound interacts with the body’s cannabinoid system, specifically the CB 1 and CB 2 receptors, which play a role in regulating nausea and various other physiological functions. While THC is widely used for both medicinal and recreational purposes, its consumption is subject to differing cultural perspectives and legal regulations. Research into the health impacts of THC is ongoing, with studies exploring its effects on respiratory health and chronic pain, among other areas.
Users may experience a range of short-term effects, such as increased appetite and altered sensory perception, while potential long-term consequences could involve respiratory issues or dependency. Importantly, the effects of THC can vary significantly based on individual health conditions and the presence of other substances, highlighting the complexity of its use and research.
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Delta-9-tetrahydrocannabinol
ALSO KNOWN AS: THC, dronabinol (Marinol), nabilone (Cesamet), Cannabis sativa, medical marijuana; slang terms include bud, ganja, grass, hemp, herb, pot, reefer, sinsemilla, weed; there are also many names signifying different growing regions and qualities of marijuana
DEFINITION: Delta-9-tetrahydrocannabinol (THC), the psychoactive substance that is the active ingredient in the plant Cannabis sativa (marijuana), is debated as a viable medical treatment. Cancer patients use substances containing THC and its synthetic and derivative forms to relieve nausea and vomiting. Patients with acquired immunodeficiency syndrome (AIDS) and multiple sclerosis also use these substances to combat weight loss.
Delivery routes: Cesamet (Nabilone) pills are taken orally in one or two milligram (mg) tablets. Marinol (dronabinol) is available in 2.5mg, 5mg, and 10mg pills, as well as an oral solution. Dried forms of marijuana, including buds of flowers and leaves, pieces of leaves, seeds, and stems, are smoked in marijuana cigarettes or pipes, burned and vaporized using other means or ingested in foods such as brownies or cookies. Cannabis sativa also may be used to produce hashish, or hash—a resinous substance typically in block or oil form that is smoked or consumed orally.
Oral forms are often used to mitigate nausea, which may accompany all forms of cancer and the chemotherapeutic drugs used to treat them. Non-oral forms, such as smoking, may be contraindicated for some types of cancer, such as lung cancers. Use may also be contraindicated in the presence of other medical and psychiatric conditions.
How this compound works: The human body has a cannabinoid system that includes two G protein–coupled receptors called CB1 and CB2 receptors (or CNR1 and CNR2). CB1 receptors are located in the central and peripheral nervous system, as well as in some other peripheral tissues. CB2 receptors are located mainly in peripheral immune cells, although some are also found in the brain and the gastrointestinal system. Both CB1 and CB2 receptors are involved in nausea and vomiting, interacting with other neurotransmitters affecting both the central nervous system and the gastrointestinal system. Products containing THC, its derivatives, or its synthetic forms are understood to affect the cannabinoid system as a whole and via these CB1 and CB2 receptors.
Cannabis sativa is a plant whose history spans centuries across diverse cultures. The plant itself has many purposes, so its worldwide presence is understandable. It has been used in spiritual and religious ceremonies in some cultures, for medicinal purposes in others, and as a recreational drug in many. In some cultures, it is an illicit substance or is highly controlled or regulated, depending on its form. In the United States, marijuana is the most widely used illicit drug. Effects may differ substantially depending on the concurrent use of other substances, whether legal, illicit, or medicinal, and the presence of physical or mental illnesses.
For many years, marijuana use was thought to be associated with cancers, particularly those of the head, neck, and lungs, such as those commonly associated with tobacco products. Contemporary scientific reviews and studies suggest, however, that such assertions are more cautionary and tentative, and a forty-year cohort study concluded that marijuana use might elevate the risk of lung cancer but could not establish a connection with any certainty. In fact, no studies have shown a definitive link between long-term marijuana use and cancer. As with other forms of smoking, however, it is associated with increased respiratory infections and other physical changes. In addition, risks associated with secondhand smoke are still suspect, and marijuana and tobacco contain many of the same carcinogens. Therefore, caution is recommended regarding any marijuana use.
Research concerning marijuana, health, and medicinal efficacy is ongoing. Scientists need better methods to estimate the amount of marijuana smoked to more formally evaluate dose-response issues. This is problematic for epidemiologic and naturalistic studies of marijuana when neither the quality nor the level of active ingredient per amount is set at a known standard. Longitudinal studies are also needed to understand the long-term health impacts of marijuana. Ongoing areas of research include improving respiratory rates in patients with moderate-to-severe obstructive sleep apnea, preventing the proliferation of breast cancer, and reducing pain in fibromyalgia and chronic neuropathic patients.
Side effects: Short-term effects may vary by the user but often include changes in sensory experiences, increases in appetite, relaxation, increased feelings of pleasure, decreases in feelings of nausea, memory and learning difficulties, panic, anxiety, coordination problems, and impaired problem-solving. Long-term effects may include abuse or dependence, motivational problems, daily cough, phlegm problems, respiratory problems, and impact on the immune system. Notably, these effects are what would be observed in normal users, that is, individuals without other significant physical or mental health problems who are not using other substances. The effects might differ in meaningful ways in individuals with other characteristics, such as physical or psychiatric problems.
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