Tetrahydrocannabinol in the context of "Cannabis"

Hemp, or industrial hemp, is a plant in the botanical class of Cannabis sativa cultivars grown specifically for industrial and consumable use. It can be used to make a wide range of products. Along with bamboo, hemp is among the fastest growing plants on Earth. It was also one of the first plants to be spun into usable fiber 50,000 years ago. It can be refined into a variety of commercial items, including paper, rope, textiles, clothing, biodegradable plastics, paint, insulation, biofuel, food, and animal feed.

Although chemotype I cannabis and hemp (types II, III, IV, V) are both Cannabis sativa and contain the psychoactive component tetrahydrocannabinol (THC), they represent distinct cultivar groups, typically with unique phytochemical compositions and uses. Hemp typically has lower concentrations of total THC and may have higher concentrations of cannabidiol (CBD), which potentially mitigates the psychoactive effects of THC. The legality of hemp varies widely among countries. Some governments regulate the concentration of THC and permit only hemp that is bred with an especially low THC content into commercial production.

Smoking is a human behavior which involves the combustion of a substance, usually plant material, and the inhalation of resulting fumes. Today smoking is mostly practiced by rolling the dried leaves of the tobacco plant into a cigarette. Other forms of tobacco smoking include the use of a smoking tobacco with a pipe or cigar, or using a bong. Cigarette smokers almost always inhale the smoke; most pipe and cigar smokers do not inhale.

Smoking is primarily practiced as a route of administration for psychoactive chemicals because the active substances within the burnt, dried plant leaves (or other chemical) can vaporize into a gaseous state and be delivered into the respiratory tract, where they are rapidly absorbed into the bloodstream through the lungs and can reach the central nervous system. In the case of tobacco smoking, these active substances are a mixture of aerosol particles that include the pharmacologically active alkaloid nicotine, which stimulates the nicotinic acetylcholine receptors in the brain, and other non-psychoactive chemicals that result from combustion. Other notable drugs inhaled via smoking include tetrahydrocannabinol (from cannabis), morphine (from opium) cocaine (from crack), and methamphetamine. Designer drugs, or "research chemicals", can also be smoked.

Cannabis (/ˈkænəbɪs/), commonly known as marijuana (/ˌmærəˈwɑːnə/), weed, pot, and ganja, among other names, is a non-chemically uniform psychoactive drug from the Cannabis plant. Native to Central or South Asia, cannabis has been used as a drug for both recreational and entheogenic purposes and in various traditional medicines for centuries. Tetrahydrocannabinol (THC) is the main psychoactive component of cannabis, which is one of the 483 known compounds in the plant, including at least 65 other cannabinoids, such as cannabidiol (CBD). Cannabis can be used by smoking, vaporizing, within food, or as an extract.

Cannabis has various mental and physical effects, which include euphoria, altered states of mind and sense of time, difficulty concentrating, impaired short-term memory, impaired body movement (balance and fine psychomotor control), relaxation, and an increase in appetite. Onset of effects is felt within minutes when smoked, but may take up to 90 minutes when eaten (as orally consumed drugs must be digested and absorbed). The effects last for two to six hours, depending on the amount used. At high doses, mental effects can include anxiety, delusions (including ideas of reference), hallucinations, panic, paranoia, and psychosis. There is a strong relation between cannabis use and the risk of psychosis, though the direction of causality is debated. Physical effects include increased heart rate, difficulty breathing, nausea, and behavioral problems in children whose mothers used cannabis during pregnancy; short-term side effects may also include dry mouth and red eyes. Long-term adverse effects may include addiction, decreased mental ability in those who started regular use as adolescents, heart disease, chronic coughing, susceptibility to respiratory infections, and cannabinoid hyperemesis syndrome.

Hallucinogens, also known as psychedelics, entheogens, or historically as psychotomimetics, are a large and diverse class of psychoactive drugs that can produce altered states of consciousness characterized by major alterations in thought, mood, and perception as well as other changes. Hallucinogens are often categorized as either being psychedelics, dissociatives, or deliriants, but not all hallucinogens fall into these three classes.

Examples of hallucinogens include psychedelics or serotonin 5-HT_2A receptor agonists like LSD, psilocybin, mescaline, and DMT; dissociatives or NMDA receptor antagonists like ketamine, PCP, DXM, and nitrous oxide; deliriants or antimuscarinics like scopolamine and diphenhydramine; cannabinoids or cannabinoid CB₁ receptor agonists like THC, nabilone, and JWH-018; κ-opioid receptor agonists like salvinorin A and pentazocine; GABA_A receptor agonists like muscimol and gaboxadol; oneirogens like ibogaine and harmaline; and others like nutmeg, carbogen, glaucine, and hallucinogenic bolete mushrooms.

Cannabidiol (CBD) is a phytocannabinoid, one of 113 identified cannabinoids in Cannabis, along with tetrahydrocannabinol (THC), and accounts for up to 40% of the plant's extract. Medically, it is an anticonvulsant used to treat two rare forms of childhood epilepsy. It was discovered in 1940. Clinical research on CBD has included studies related to the treatment of anxiety, addiction, psychosis, movement disorders, and pain, but there is insufficient high-quality evidence that CBD is effective for these conditions. CBD is sold as an herbal dietary supplement and promoted with unproven claims of particular therapeutic effects.

Cannabidiol can be taken internally in multiple ways, including by inhaling cannabis smoke or vapor, swallowing it by mouth, and through use of an aerosol spray inside the cheek. It may be supplied as CBD oil containing only CBD as the active ingredient (excluding THC or terpenes), CBD-dominant hemp extract oil, capsules, dried cannabis, or prescription liquid solution. CBD does not have the same psychoactivity as THC, and can modulate the psychoactive effects of THC on the body if both are present. Conversion of CBD to THC can occur when CBD is heated to temperatures between 250–300 °C, potentially leading to its partial transformation into THC.

In chemistry, a space-filling model, also known as a calotte model, is a type of three-dimensional (3D) molecular model where the atoms are represented by spheres whose radii are proportional to the radii of the atoms and whose center-to-center distances are proportional to the distances between the atomic nuclei, all in the same scale. Atoms of different chemical elements are usually represented by spheres of different colors.

Space-filling calotte models are also referred to as CPK models after the chemists Robert Corey, Linus Pauling, and Walter Koltun, who over a span of time developed the modeling concept into a useful form. They are distinguished from other 3D representations, such as the ball-and-stick and skeletal models, by the use of the "full size" space-filling spheres for the atoms. The models are tactile and manually rotatable. They are useful for visualizing the effective shape and relative dimensions of a molecule, and (because of the rotatability) the shapes of the surface of the various conformers. On the other hand, these models mask the chemical bonds between the atoms, and make it difficult to see the structure of the molecule that is obscured by the atoms nearest to the viewer in a particular pose. For this reason, such models are of greater utility if they can be used dynamically, especially when used with complex molecules (e.g., see the greater understanding of the molecules shape given when the THC model is clicked on to rotate).

The first pass effect (FPE), also known as first-pass metabolism (FPM) or presystemic metabolism, is a phenomenon of drug metabolism at a specific location in the body which leads to a reduction in the concentration of the active drug before it reaches the site of action or systemic circulation. The effect is most associated with orally administered medications, but some drugs still undergo first-pass metabolism even when delivered via an alternate route (e.g., IV, IM, etc.). During this metabolism, drug is lost during the process of absorption which is generally related to the liver and gut wall. The liver is the major site of first pass effect; however, it can also occur in the lungs, vasculature or other metabolically active tissues in the body.

Notable drugs that experience a significant first pass effect are buprenorphine, chlorpromazine, cimetidine, diazepam, ethanol (drinking alcohol), imipramine, insulin, lidocaine, midazolam, morphine, pethidine, propranolol, and tetrahydrocannabinol (THC).

A head shop is a store that sells drug-related paraphernalia. They emerged from the hippie counterculture in the late 1960s, and at that time, many of them had close ties to the anti-Vietnam War movement as well as groups in the marijuana legalization movement like LeMar, Amorphia, and the National Organization for the Reform of Marijuana Laws.

Products sold may include magazines (e.g., about cannabis culture, cannabis cultivation, tattooing, and music), clothing, and home décor (e.g., posters and wall hangings illustrating drug culture themes such as cannabis, jam bands like The Grateful Dead, Phish, psychedelic art, etc.). Some head shops also sell oddities, such as antique walking sticks and sex toys. Since the 1980s, some head shops have sold clothing related to the heavy metal or punk subculture, such as band T-shirts and cloth patches with band logos, studded wristbands, bullet belts, and leather boots. Other items offered typically include hashish pipes, "one hitter" pipes; pipe screens; bongs (also referred to as water pipes); roach clips (used for smoking the end of a marijuana "joint"); vaporizers used for inhaling THC vapor from cannabis; rolling papers; rolling machines; small weighing scales; small ziplock baggies; cannabis grinders (i.e. herb grinders); blacklight-responsive posters and blacklights; incense; cigarette lighters; "stashes", which include a range of standard consumer products such as clocks, books, tins of cleaning powder, and toilet brushes which have hidden compartments for cannabis and non-camouflaged "stash boxes" which are tins or wooden containers for storing marijuana; and legal highs such as whipped-cream chargers (which contain nitrous oxide) and Salvia divinorum (both of which are illegal in some countries and some US states for recreational purposes). Some head shops also sell items used for home cultivation of marijuana plants, such as hydroponic equipment and lights and guidebooks on cultivation. Since the 2000s, some head shops also sell e-cigarettes and the flavoured liquids used with these devices.