Botanical name

Cannabis sativa L.

Family

Cannabaceae

Common name

Marijuana, Hemp, Cannabis, Weed, Herb, Ganja, Mary Jane

Information about the plant

The hemp plant has been used for fiber and oil production for thousands of years and is therefore found worldwide in temperate and tropical regions. It likely originated in the temperate regions of Central Asia to Northwest India. The plant can grow up to 3.5 m tall. The long-stemmed leaves are opposite on a rough, branched stem, palmate with 5 to 11 fingers, and only 3-parted or undivided at the shoot tips. The individual leaflets are lanceolate, long-pointed and coarsely serrated. The hemp plant is dioecious, i.e. there are male and female plants. The male plant’s flowers are light yellow-green and arranged in loose panicles with a deep 5-part perigone. Female plants are larger than the males and have denser foliage; the female flowers are discreetly greenish, enclosed by bracts, and form a densely packed false spike (photo). This feels slightly sticky due to a resin secreted by glandular hairs. The resin contains the addictive Δ9-tetrahydrocannabinol (Δ9-THC); it belongs to the group of cannabinoids (see "Constituents of the herbal drug").

The stalks of cultivated hemp, C. sativa ssp. sativa, are used for fiber production; their firm 5 to 55 cm long fibers are used to make ropes, cables, nets, twines, and twists. Nowadays, cultivated hemp has been bred to contain minimal amounts of the addictive Δ9-THC. In any case, only varieties low in Δ9-THC are permitted for cultivation in the EU for fiber production, and only under strict official supervision. The small gray fruits of the hemp plant, usually called hemp "seeds", are commercialized as bird food; the oil extracted from them is used as cooking oil or for the production of green soft soap and, as it dries easily like linseed oil, also for paints. The "seeds" contain no cannabinoids, at most through contamination with the resin of the flowers.

Under tropical growing conditions, the glandular heads of the glandular hairs of the female flowers and fruit form significantly more Δ9-THC than when grown in temperate zones. The resin of Indian hemp - C. sativa subsp. indica (Lam.) E.Small & Cronquist - contains particularly high concentrations of Δ9-THC; this subspecies is a supplier of narcotics. The leaves of the shoot tips are also covered with glandular hairs, albeit only slightly, and contain some Δ9-THC. In the drug scene, the cut shoot tips with female inflorescences are sold and consumed as "marijuana", containing 0.5 to 2 % Δ9-THC. Etymologically, marijuana is derived from "Maria" and "Johanna", referring to the dioecious nature of the plant. To obtain "hashish" (etymologically from "assassin"), the Δ9-THC-containing brown resin is rubbed off the tips of the female shoots and pressed into sticks or slabs; it contains 2 to 8% Δ9-THC. As the cannabinoids are lipophilic (= fat-soluble), they can be extracted from the female shoot tips with fatty oil; the resulting product is "cannabis oil", in which the cannabinoids are highly concentrated; it contains 20% and more Δ9-THC.

Cannabis as a medicinal plant - legal situation
With the German Act on the Amendment of Narcotics Law and other Regulations (Gesetz zur Änderung betäubungsmittelrechtlicher und anderer Vorschriften), which came into force on March 10, 2017, the legislator has expanded the options for prescribing cannabis-based medicines. Its central message is that medicinal cannabis flowers or cannabis extracts can be prescribed for medical purposes on a narcotics prescription. However, doctors may only prescribe cannabis products to patients for whom other therapeutic options have been exhausted and if an improvement in symptoms or the course of the disease is to be expected. With this law, cannabis flowers and cannabis extracts in standardized pharmaceutical quality now have the status of a medicinal product and can, therefore, be stocked, processed and dispensed to patients in pharmacies. Previously, cannabis and Δ9-THC (= dronabinol) could only be used medicinally with a special permit from the Federal Opium Agency - located within the Federal Institute for Drugs and Medical Devices (BfArM, Bundesinstitut für Arzneimittel und Medizinprodukte). A state cannabis agency has been set up within the BfArM to coordinate and control the cultivation and distribution of cannabis. Cannabis as an illegal intoxicant drug remains prohibited, as does home cultivation for medicinal purposes.
On April 1, 2024, the Cannabis Act came into force, which provides, among other things, that medicinal cannabis is no longer considered a narcotic, but is only subject to prescription. This applies to cannabis flowers, cannabis extracts and Δ9-THC (dronabinol) as well as finished cannabis medicinal products.

Medicinally used parts of plants (herbal drug)

The flowering, dried shoot tips of the female plants are medicinally used (cannabis flowers - Cannabis flos). They are cut off during the flowering stage and dried, if necessary, trimmed before drying. They characteristically feel sticky due to the resin and have a spicy and pungent smell. Cannabis flowers for medicinal purposes mainly come from high-quality varieties grown in greenhouses.

Constituents of the herbal drug

Cannabis flowers contain around 120 different cannabinoids, classifiable into around 10 different types; they are enriched in the resin. The main addictive cannabinoid (-)-trans-Δ9-tetrahydrocannabinol (Δ9-THC; INN: dronabinol) is responsible for the psychotropic effect (content in cannabis flowers 0.5 to 2%). It is formed from (-)-trans-Δ9-tetrahydrocannabinolic acid (Δ9-THC acid), which is also present in the resin. When cannabis flowers (marijuana) are smoked, Δ9-THC is also formed from the Δ9-THC acid through thermal decarboxylation. Other cannabinoids are cannabidiol (the most important non-psychoactive cannabinoid), cannabinol and cannabinoids of the cannabichromene and cannabigerol type, as well as cannabinoids of other types. The characteristic smell is due to the essential oil with mono- and sesquiterpenes contained in the drug; spirans, dihydrostilbenes and compounds with a 9,10-dihydrophenanthrene structure, as well as polyamines, protoalkaloids and flavonoids are also present.

Quality of the drug

The quality of cannabis flowers (Cannabis flos) and of standardized cannabis extract (Cannabis extractum normatum) is specified in the German Pharmacopoeia (DAB, Deutschen Arzneibuch). In the case of cannabis flowers, the content of Δ9-THC and cannabidiol, as well as the content of the chemical precursors ∆9-tetrahydrocannabinolic acid and cannabidiolic acid, must be declared on the container. For the standardized cannabis extract, the Δ9-THC content may be between 1% and 25% and must be declared on the container, as well as the presence of cannabidiol (without specified amount content requirements).

Medical applications

Recognised medical use

Indications (pharmacopoeia commentary): Treatment and prophylaxis of vomiting during chemotherapy, loss of appetite and weight loss in AIDS patients, relief of pain and spasms in patients with multiple sclerosis, add-on therapy for tumor pain; neuropathic pain.

Traditional use

Due to the content of highly psychotropic Δ9-THC, cannabis flowers cannot be classified as a traditional herbal medicinal product within the meaning of Article 16a of Directive 2001/83/EC.

Herbal drug preparations in finished dosage forms

None; only finished medicinal products with isolated Δ9-THC (INN: dronabinol) are available on the market.

Dosage

The dosage must be calculated individually.

Preparation of a tea

Not applicable

Notes

Side effects very frequently include tiredness, dizziness, headaches, nausea, depression, and dry mouth; frequently also tachycardia (palpitations), drop in blood pressure, muscle relaxation and increased appetite.
Warning: the ability to use machines and drive vehicles is restricted.
Attention must also be drawn to interactions with other medicines, e.g. insulinotropic antidiabetics, benzodiazepines, vitamin K antagonists, and proton pump inhibitors.

Further literature

Commentary on the German Pharmacopoeia (Cannabis flowers, Standardized cannabis extract)