Hemp / CBD
Cannabis sativa
Description
overall appearance
An erect annual herb growing 1–5 m tall depending on variety and cultivation conditions, with a characteristic palmate leaf silhouette and a pungent, resinous aroma. Hemp cultivars tend toward taller, less branched growth with lower resin content compared to drug-type varieties.
roots
Taproot system with extensive lateral branching; primary taproot can penetrate 30–60 cm into well-drained soil, improving soil structure and sequestering carbon
stem
Hollow, ridged, and fibrous; 4–20 mm in diameter, covered in short stiff hairs; bark contains long bast fibers used historically for rope and textiles
leaves
Palmate compound leaves with 5–9 lanceolate serrate leaflets each 8–15 cm long; alternately arranged on the stem; upper leaves may have fewer leaflets; covered in fine trichomes on both surfaces
flowers
Dioecious; male flowers are small, yellow-green, clustered in loose panicles; female flowers are green, enclosed in bracts bearing secretory trichomes; flowers appear in summer to early autumn
fruits/seeds
Achene (hemp seed) 3–5 mm, grey-green to brown, covered by a persistent perianth; seeds contain 30–35% oil by weight and are nutritionally dense
Active Compounds
Traditional Uses
- Ancient Chinese medicine (Shennong Bencao Jing): seeds used as tonic food and to treat constipation and wasting diseases
- Ayurvedic tradition: 'Vijaya' used to stimulate appetite, relieve pain, and as a sleep aid
- European folk medicine: poultices of seeds and leaves applied for skin inflammation and joint pain
- Scythian steam baths (Herodotus, 5th c. BCE): burned seeds inhaled for intoxication and ritual cleansing
- Medieval European herbalism: seeds and oil used for digestive complaints and as a nutritive tonic
- Traditional Islamic medicine: anti-inflammatory and analgesic for headaches and neuralgia
- Indigenous North American traditions: fiber and seeds as food and material culture; some groups used leaf preparations for pain
- Traditional use across Central Asia for insomnia, anxiety, and muscle spasm relief
Modern Applications
- FDA-approved CBD (Epidiolex) for treatment-resistant epilepsy (Dravet syndrome, Lennox-Gastaut syndrome) — RCT evidence
- Anxiety reduction: multiple RCTs showing CBD reduces anxiety in social anxiety disorder and PTSD
- Anti-inflammatory and analgesic: topical CBD reduces pain and inflammation in preclinical and small clinical studies
- Neuroprotective effects studied in Parkinson's disease, Alzheimer's, and multiple sclerosis
- Hemp seed oil: favorable omega-6:omega-3 ratio (3:1) supports cardiovascular health
- Sleep quality improvement: low-dose CBD studied for insomnia and sleep disorders
- Antiemetic effects: CBD reduces chemotherapy-induced nausea (preliminary clinical data)
- Acne reduction: CBD inhibits sebocyte proliferation and sebum production in vitro
⚠️ Safety Information
Contraindications
- Pregnancy and breastfeeding: insufficient safety data; avoid CBD products
- Liver disease: CBD is hepatically metabolized; elevated liver enzymes reported at high doses
- Children under 2 years: except under medical supervision for seizure disorders
- Known hypersensitivity to Cannabis species
- Pre-existing psychiatric conditions (schizophrenia, psychosis): monitor closely; high-THC products contraindicated
- Avoid high-dose CBD before or during surgical procedures due to platelet effects
Side Effects
- Drowsiness and sedation, particularly at doses >150 mg CBD
- Dry mouth (xerostomia) at therapeutic doses
- Diarrhea and gastrointestinal upset reported in clinical trials
- Elevated liver enzymes (ALT/AST) at doses >20 mg/kg/day in epilepsy trials
- Reduced appetite and weight changes in some users
- Interaction with drug metabolism leading to altered plasma levels of co-medications
Drug Interactions
- CYP450 inhibitor (CYP3A4, CYP2C19, CYP2D6): increases plasma levels of warfarin, clobazam, valproate, and many other drugs — requires therapeutic drug monitoring
- CNS depressants (benzodiazepines, opioids, alcohol): additive sedation
- Anticoagulants (warfarin, heparin): CBD inhibits warfarin metabolism, increasing bleeding risk
- Antiepileptics (clobazam, valproate): pharmacokinetic interactions leading to dose adjustment needs
- Immunosuppressants (cyclosporine, tacrolimus): CBD alters metabolism, monitor serum levels
Parts Used
- Aerial flowers and leaves (CBD-rich extract)
- Seeds and seed oil
- Root (traditional decoction)
- Fiber (topical applications, poultices)
Preparation Methods
CBD tincture (sublingual): 15–50 mg CBD per dose, 1–2× daily for anxiety/pain/sleep
CBD capsules/softgels: 25–75 mg CBD daily, standardized extract
Topical CBD cream or balm: 3–8% CBD concentration applied to affected area 2–3× daily
Hemp seed oil (culinary): 1–2 tablespoons daily in food for nutritional omega fatty acids
CBD isolate powder: 10–100 mg in water or food, precise dosing
Full-spectrum hemp extract (oral): 15–30 mg CBD equivalent twice daily; includes minor cannabinoids and terpenes for entourage effect
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