Plant Profile

Hemp

Cannabis sativa
Family: Cannabaceae  ·  Parts used: Flower, Leaf, Seed  ·  Also known as: industrial hemp, cannabis

The complete database record: 3 documented constituents, 4 pharmacological actions, 7 traditional / indicated uses, with 21 cited sources.

Botanical Description

Erect annual herb with a distinctive palmately compound leaf of narrow, serrated leaflets. The plant is usually dioecious (separate male and female plants); female plants develop dense, resinous flower clusters, while male plants bear looser pollen-releasing flowers. The seed (achene) is small, hard-shelled and oil-rich.[14]

Height: 1-5 m, depending on variety and cultivation
Habit: Erect, fast-growing annual herb
Leaves: Palmately compound, narrow serrated leaflets
Flowers: Dioecious; female flowers in dense resinous clusters, male flowers looser and pollen-releasing
Stem: Erect, fibrous, often ridged
Root: Taproot with fibrous lateral roots
Fruit: Small, hard-shelled, oil-rich achene (seed)
Flowering Period: Late summer to autumn

Habitat & Distribution

Believed native to Central Asia; now cultivated worldwide, with industrial hemp (low-THC cultivars) grown in temperate climates for fibre, seed and cannabinoid extraction, subject to varying legal regulation by jurisdiction.[14]

Harvesting

Flowers (and resin-bearing leaves) are harvested at peak resin/cannabinoid content, typically as the flower clusters mature in late summer to autumn; seed is harvested once mature and dried, then pressed for oil or used whole.[14]

Parts: Flower, Leaf, Seed
Season: Late summer to autumn

Key Constituents

Cannabinoids (THC, CBD and related compounds)[14, 17]

The characteristic bioactive compounds of the resin-bearing flowers, varying widely in ratio and concentration between cultivars; THC is psychoactive, CBD is not.

Terpenes[14]

Aromatic terpenes contribute to the plant's characteristic scent and may modulate cannabinoid effects.

Terpenes / terpenoidsEssential (volatile) oil
Seed oil fatty acids[14]

Hemp seed is rich in polyunsaturated fatty acids (including omega-3 and omega-6), giving the pressed seed oil its nutritional value; essentially free of psychoactive cannabinoids.

Pharmacological Actions

Analgesic (pain relief)[1, 7, 9, 12, 14, 17]
Anti-inflammatory[6, 8, 10, 12, 14, 17]
Antioxidant[5, 14, 17]
Sedative / sleep support[14, 17]

Traditional & Indicated Uses

Arthritis / joint pain

inferred from anti-inflammatory action

Mechanistic Exclude Ids: REF-0044, REF-0058, REF-2138
Evidence: 1
Label: Arthritis / joint pain

more plants for arthritis / joint pain →detailed sources →

Back pain

inferred from analgesic action

Mechanistic Exclude Ids: REF-0044, REF-0058
Evidence: 1
Label: Back pain

more plants for back pain →detailed sources →

Cardiovascular / heart health[14]Preliminary · 2/10
Evidence: 2
Label: Cardiovascular / heart health

more plants for cardiovascular / heart health →detailed sources →

Headache

inferred from analgesic action

Mechanistic Exclude Ids: REF-0044, REF-0058
Evidence: 1
Label: Headache

more plants for headache →detailed sources →

Inflammation (general)[14]Preliminary · 2/10

inferred from anti-inflammatory action

Mechanistic Exclude Ids: REF-0058
Evidence: 2
Label: Inflammation (general)

more plants for inflammation (general) →detailed sources →

Pain (general)
Mechanistic Exclude Ids: REF-0044, REF-0058
Evidence: 1
Label: Pain (general)

more plants for pain (general) →detailed sources →

Skin irritation[14]Preliminary · 2/10

inferred from anti-inflammatory action

Mechanistic Exclude Ids: REF-0058
Evidence: 2
Label: Skin irritation

more plants for skin irritation →detailed sources →

Traditional Use & History

Cannabis/hemp has a long multi-cultural history as a fibre, food and medicinal plant, traditionally used for pain, muscle spasm, sleep and appetite, alongside industrial use of the fibre and seed. Modern cannabinoid research, particularly on THC and CBD, has substantially expanded the evidence base for pain, spasticity and specific seizure disorders.[14, 17]

Preparations

Seed / seed oil[14]

Whole or hulled seed, or cold-pressed seed oil, used as a nutritional food source (essentially free of psychoactive cannabinoids).

Standardised cannabinoid extract[17]

Extract standardised to specific cannabinoid content (e.g. CBD), used in regulated medicinal products; regulatory status varies widely by jurisdiction and product type.

Safety, Cautions & Contraindications

Safety note[14, 17, 18]Caution

Industrial hemp (low-THC cannabis) seed oil and seeds are generally safe as food. CBD products derived from hemp may interact with medications metabolised by cytochrome P450 liver enzymes, including common anticoagulants, antiepileptics, and immunosuppressants. THC-containing preparations impair driving and are regulated or prohibited in many jurisdictions. Not recommended during pregnancy or breastfeeding. Quality and cannabinoid content vary widely between hemp products.

Safety note[14, 17, 18, 19]Caution

Duke (2002) rates cannabis as ++ and notes clinical evidence (score 2) for its antiemetic activity, especially relevant for chemotherapy-induced nausea. Score 1 activities include analgesic, anticonvulsant, and anti-inflammatory properties. Duke highlights the legal and pharmacological complexity, noting THC as the primary psychoactive compound. Medically, synthetic cannabinoids (dronabinol, nabilone) are clinically approved for nausea and anorexia. Duke cautions that while the plant has genuine therapeutic potential, psychoactive effects, legal restrictions, and risk of dependence with regular use must be considered (Duke, 2002).

Herb-Drug Interactions

Sedatives Cns Depressants[20, 21]Caution
Mechanism: Cannabis (and CBD) commonly cause drowsiness and sedation; taken with sedatives, sleeping tablets, opioids or other central-nervous-system depressants (including alcohol) it may add to drowsiness and slowed reactions.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Anticonvulsants[20]Caution
Mechanism: Cannabidiol (CBD) interacts with anti-seizure medicines - notably raising exposure to clobazam - and can add to sedation; anyone combining cannabis/CBD with anticonvulsants should be monitored and doses reviewed by their clinician.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03

Harvest Readiness

[15]

Part: flower
Signals: Harvest the female flowering tops when most of the resin glands (trichomes) have turned from clear to milky/cloudy, with only a small fraction turning amber - the point of peak cannabinoid and terpene development.
Basis: both
Constituent Note: Peak cannabinoid maturity is judged by trichome colour: '80-90% of trichomes are milky/cloudy' with '5-15% of trichomes are amber' (Ed Rosenthal, REF-3222).
Source Quote: When most trichomes are milky with a small percentage turning amber, cannabinoids and terpenes have reached peak development.
Species Confirmed:
Notes: Ed Rosenthal (REF-3222) on judging cannabis ripeness by trichome maturity. The source uses the vernacular 'cannabis' rather than the binomial Cannabis sativa, so species_confirmed is false pending a binomial-level source. Single source -> provisional.

[16]

Part: seed
Signals: Harvest the seed from the female plants when it is ripe - most of it falls off when the plant is shaken; collect in the early morning while the fruits are turgid.
Basis: traditional
Source Quote: Seed is harvested from the female plants when most of it falls off when the plant is shaken.
Species Confirmed: 1
Notes: Useful Temperate Plants (REF-3221) for Cannabis sativa. Single source -> provisional.
Part: leaf
Notes: GAP (documented dead end, re-searched 2026-08-15). No source states a readiness stage for the cannabis LEAF as a part in its own right. The sourced signals are for the female flower (trichome maturity), the seed (falls when ripe) and the fibre/male-plant harvest; the fan leaves are taken with the flowering tops. A peer-reviewed morphological characterisation of the complete Cannabis sativa life cycle (Hesami et al., Plants 2023) tracks the life cycle but does not address fan-leaf senescence at harvest. Recorded as a dead end rather than asserting the leaf inherits the flowering-top stage.

External Identifiers

References & Sources

  1. Rock, E.M. and Parker, L.A (2021) 'Constituents of Cannabis sativa', Advances in Experimental Medicine and Biology, 1264, pp. 1-13. doi:10.1007/978-3-030-57369-0_1 Traditional / reference
    https://doi.org/10.1007/978-3-030-57369-0_1
  2. Castillo-Arellano, J., Canseco-Alba, A., Cutler, S.J. and León, F (2023) 'The Polypharmacological Effects of Cannabidiol', Molecules, 28(7), pp. 3271. doi:10.3390/molecules28073271 Traditional / reference
    https://doi.org/10.3390/molecules28073271
  3. Pagano, C., Navarra, G., Coppola, L., Avilia, G. et al (2022) 'Cannabinoids: Therapeutic Use in Clinical Practice', International Journal of Molecular Sciences, 23(6), pp. 3344. doi:10.3390/ijms23063344 Traditional / reference
    https://doi.org/10.3390/ijms23063344
  4. ElSohly, M.A., Radwan, M.M., Gul, W., Chandra, S. and Galal, A (2017) 'Phytochemistry of Cannabis sativa L', Progress in the Chemistry of Organic Natural Products, 103, pp. 1-36. doi:10.1007/978-3-319-45541-9_1 Meta-analysis / review
    https://doi.org/10.1007/978-3-319-45541-9_1
  5. Viana, M.D.B., de Aquino, P.E.A., Estadella, D., Ribeiro, D.A. and Viana, G.S.D.B (2022) 'Cannabis sativa and cannabidiol: a therapeutic strategy for the treatment of neurodegenerative diseases?', Medical Cannabis and Cannabinoids, 5(1), pp. 207-219. doi:10.1159/000527335 Meta-analysis / review
    https://doi.org/10.1159/000527335
  6. Alves, P., Amaral, C., Teixeira, N. and Correia-da-Silva, G (2020) 'Cannabis sativa: much more beyond delta-9-tetrahydrocannabinol', Pharmacological Research, 157, pp. 104822. doi:10.1016/j.phrs.2020.104822 Meta-analysis / review
    https://doi.org/10.1016/j.phrs.2020.104822
  7. Odieka, A.E., Obuzor, G.U., Oyedeji, O.O., Gondwe, M., Hosu, Y.S. and Oyedeji, A.O (2022) 'The medicinal natural products of Cannabis sativa Linn.: a review', Molecules, 27(5), pp. 1689. doi:10.3390/molecules27051689 Meta-analysis / review
    https://doi.org/10.3390/molecules27051689
  8. Nuutinen, T (2018) 'Medicinal properties of terpenes found in Cannabis sativa and Humulus lupulus', European Journal of Medicinal Chemistry, 157, pp. 198-228. doi:10.1016/j.ejmech.2018.07.076 Meta-analysis / review
    https://doi.org/10.1016/j.ejmech.2018.07.076
  9. Liktor-Busa, E., Keresztes, A., LaVigne, J., Streicher, J.M. and Largent-Milnes, T.M (2021) 'Analgesic potential of terpenes derived from Cannabis sativa', Pharmacological Reviews, 73(4), pp. 98-126. doi:10.1124/pharmrev.120.000046 Meta-analysis / review
    https://doi.org/10.1124/pharmrev.120.000046
  10. Martinelli, G., Magnavacca, A., Fumagalli, M., Dell'Agli, M., Piazza, S. and Sangiovanni, E (2021) 'Cannabis sativa and skin health: dissecting the role of phytocannabinoids', Planta Medica, 88(7), pp. 492-506. doi:10.1055/a-1420-5780 Meta-analysis / review
    https://doi.org/10.1055/a-1420-5780
  11. Andre, C.M., Hausman, J.F. and Guerriero, G (2016) 'Cannabis sativa: the plant of the thousand and one molecules', Frontiers in Plant Science, 7, pp. 19. doi:10.3389/fpls.2016.00019 Meta-analysis / review
    https://doi.org/10.3389/fpls.2016.00019
  12. Bonini, S.A., Premoli, M., Tambaro, S., Kumar, A., Maccarinelli, G., Memo, M. and Mastinu, A (2018) 'Cannabis sativa: a comprehensive ethnopharmacological review of a medicinal plant with a long history', Journal of Ethnopharmacology, 227, pp. 300-315. doi:10.1016/j.jep.2018.09.004 Meta-analysis / review
    https://doi.org/10.1016/j.jep.2018.09.004
  13. Bergamaschi, M.M., Queiroz, R.H.C., Zuardi, A.W. and Crippa, J.A.S (2011) 'Safety and side effects of cannabidiol, a Cannabis sativa constituent', Current Drug Safety, 6(4), pp. 237-249. doi:10.2174/157488611798280924 Meta-analysis / review
    https://doi.org/10.2174/157488611798280924
  14. Cerino, P., Buonerba, C., Cannazza, G. et al (2021) 'A review of hemp as food and nutritional supplement', 6(1), pp. 19--27. doi:10.1089/can.2020.0001 Preclinical
    https://doi.org/10.1089/can.2020.0001
  15. Rosenthal, Ed 'Harvesting Cannabis by Trichome Maturity'. Available at: https://www.edrosenthal.com/ask-ed-blog/harvesting-cannabis-by-trichome-maturity Traditional / reference
    https://www.edrosenthal.com/ask-ed-blog/harvesting-cannabis-by-trichome-maturity
  16. Fern, Ken 'Cannabis sativa (Hemp) — Useful Temperate Plants'. Available at: https://temperate.theferns.info/plant/Cannabis+sativa Traditional / reference
    https://temperate.theferns.info/plant/Cannabis+sativa
  17. Devinsky, O., Cross, J.H., Laux, L. et al (2017) 'Trial of cannabidiol for drug-resistant seizures in the Dravet syndrome', 376(21), pp. 2011--2020. Randomized trial
    https://scholar.google.com/scholar?q=Trial%20of%20cannabidiol%20for%20drug-resistant%20seizures%20in%20the%20Dravet%20syndrome
  18. Royal Botanic Gardens, Kew (n.d.). Available at: https://powo.science.kew.org Traditional / reference
    https://powo.science.kew.org
  19. Duke, J.A (2002) 'Handbook of Medicinal Herbs, Second Edition'. Traditional / reference
    https://scholar.google.com/scholar?q=Handbook%20of%20Medicinal%20Herbs%2C%20Second%20Edition
  20. Talwar, A., Estes, E., Aparasu, R. and Reddy, D.S (2022) 'Clinical efficacy and safety of cannabidiol for pediatric refractory epilepsy indications: A systematic review and meta-analysis', Experimental Neurology, 359, pp. 114238. doi:10.1016/j.expneurol.2022.114238 Meta-analysis / review
    https://doi.org/10.1016/j.expneurol.2022.114238
  21. Caus, M.N., Lupoae, M. and Chitescu, C.L (2026) 'Efficacy and Safety of Herbal Supplements with Anxiolytic, Antidepressant, and Sedative Action: A Review of Clinical Data and Toxicological Risks', Pharmaceuticals, 19(3), pp. 399. doi:10.3390/ph19030399 Meta-analysis / review
    https://doi.org/10.3390/ph19030399

This fact sheet is generated automatically from the Omnia Sana plant database and reflects its latest synced data. It is provided for educational purposes only and is not medical advice. How this site is built.

Selected studies & references

Educational use only. This profile summarises traditional and scientific sources for reference. It is not medical advice and not a substitute for a qualified practitioner. Some plants carry safety cautions and drug interactions - always check before use.
This profile is assembled automatically from the Omnia Sana plant database, which we curate by hand. How this site is built.
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