Nigella sativa

Nigella sativa

Common Names

  • Black cumin
  • Black caraway
  • Black seed
  • Kalonji

For Patients & Caregivers

How It Works

Black cumin seed has not been shown to treat cancer in humans.

Black cumin seed is used for cooking and in medicine in India, Arabia, and Europe. Laboratory studies have shown that some components have antioxidant and anti-inflammatory effects. Therefore, there is some speculation that black cumin seed may be useful in the treatment of cancer and protect against the side effects of radiation therapy, but these have not been proven in humans. Early phase studies suggest that black cumin seed may help to control high blood pressure, asthma, diabetes, and rheumatoid arthritis.

Purported Uses
  • To treat cancer
    Animal studies have shown that black cumin seed can stop the growth of tumor cells and reduce the incidence of tumors. However, the effects in humans are unclear.
  • To protect the body from the adverse effect of radiation therapy
    Animal studies have shown that black cumin seed oil, when injected, may protect against tissue damage caused by radiation. However, the effects in humans are unknown.
  • To decrease hypertension
    In one study in humans, daily use of black cumin seed extract for 2 months may have help to lower blood pressure in patients with mild hypertension.
  • To decrease symptoms of asthma
    An early phase study suggests black cumin seed may help to prevent the asthmatic symptoms. More research is warranted.
  • To treatment rheumatoid arthritis
    One study shows black cumin seed oil when taken orally, can help reduce symptoms of rheumatoid arthritis
Do Not Take If
  • You are taking cytochrome P450 substrate drugs: Nigella sativa may increase the risk of side effects of these drugs.
Side Effects
  • High doses of Nigella sativa caused liver and kidney damage in rats.
  • Topical use of Nigella sativa caused allergic reactions.
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For Healthcare Professionals

Scientific Name
Nigella sativa
Clinical Summary

Nigella sativa is a flowering plant found throughout India, Arabia, and Europe. The seeds, commonly known as black seeds or black cumin, are used in cooking and in traditional medicine for inflammation, infection, and cancer.

Constituents from N. sativa demonstrated immunomodulatory (1) (2) (11), antioxidant (15), antiparasitic (13) and hepatoprotective effects (14) in vitro and in animal studies. N. sativa seed may be useful in the treatment of asthma (21), hypertension (5) (10) (22), rheumatoid arthritis (26), dyspepsia (27), and diabetes (28) in humans. Thymoquinone, a major constituent of N. sativa, exhibited antiepileptic effects in children with refractory seizures (23). N. sativa may also relieve symptoms of allergic reactions (12), but allergic contact dermatitis was reported with topical use (19).

Evidence also suggests that N. sativa has anticancer properties. Thymoquinone and other constituents of the seeds reduced the growth and size of tumors in rats (4) (5) (6) (7) (8) (9). Thymoquinone also enhanced the anticancer effects of doxorubicin in certain cancer cell lines (25). N. sativa oil, when injected, demonstrated a protective effect against tissue damage caused by radiation in rats  (15). Human studies are lacking.

Adverse effects are rare, but high doses of N. sativa oil caused liver and kidney damage in rats (7).

Purported Uses
  • Antioxidant
  • Anticarcinogenic
  • Anti-inflammatory
  • Asthma, bronchitis
  • Rheumatism
  • Hypertension
  • Hepatoprotective
Mechanism of Action

Thymoquinone, one of the chief constituents of Nigella sativa oil has antioxidant effects and restored the levels of lactate dehydrogenase, glutathione, and SOD in animal models (6) (7) (9). This may also explain N. sativa’s hepatoprotective effects (3) (4). Studies have also shown that N. sativa oil has anti-inflammatory properties by inhibiting cyclooxygenase and lipoxygenase (18). An in vitro study demonstrated that nigellone, a constituent of the crude extract of N. sativa seeds, inhibited histamine release from rat peritoneal mast cells (10) and may reduce allergy symptoms in humans (12). N. sativa decreased hypertension in rats possibly due to its diuretic effects (5). It was also shown to decrease uterine smooth muscle contractions (14).

The antioxidant effect is thought to protect tissues from radiation injury (15). However, it is not clear if this would also make radiation therapy less effective. Thymoquinone administered to mice reduced the incidence of stomach tumors (7). Possible mechanisms include inhibition of DNA synthesis (7), and promotion of apoptosis by inhibiting cell growth in G1 phase (8).

The methanol extract of N. sativa exhibits in vitro estrogenic activity after naringinase treatment (30).

Adverse Reactions
  • In animals, the fixed oil of N. sativa orally administered to rats for up to 12 weeks did not produce any significant changes in hepatic enzymes and did not cause mortality (16). However, high doses may cause liver damage (29).
  • Topical use of pure oil of N. sativa caused allergic contact dermatitis in 2 people with maculopapular eczema (19).
Herb-Drug Interactions
  • Cytochrome P450 substrates: Nigella sativa inhibits CYP2D6 and CYP3A4 and can affect the intracellular concentration of drugs metabolized by these enzymes (24).
Herb Lab Interactions

In animal studies, Nigella sativa oil decreased serum glucose, triglyceride, cholesterol levels and leukocyte and platelet counts, but there was an increase in hematocrit and hemoglobin levels (16) (20).

  1. Haq A, Lobo PI, Al-Tufail M, et al. Immunomodulatory effect of Nigella sativa proteins fractionated by ion exchange chromatography. Int J Immunopharmacol 1999;21(4):283-95.

  2. Haq A, Abdulatif M, Lobo PI, et al. Nigella sativa: effect on human lymphocytes and polymorphonuclear leukocyte phagocytic activity. Immunopharmacology 1995;30(2):147-55.

  3. Ali BH and Blunden G. Pharmacological and toxicological properties of Nigella sativa. Phytother Res 2003;17(4):299-305.

  4. Dada MH and Abdel-Rahman MS. Hepatoprotective activity of thymoquinone in isolated rat hepatocytes.Toxicol Lett 1998. 95(1): p. 23-9.

  5. Badary OA, et al. Inhibition of benzo(a)pyrene-induced forestomach carcinogenesis in mice by thymoquinone. Eur J Cancer Prev 1999;8(5):435-40.

  6. Ait Mbarek L, et al. Anti-tumor properties of blackseed (Nigella sativa L.) extracts. Braz J Med Biol Res 2007;40(6):839-47.

  7. Chakravarty N. Inhibition of histamine release from mast cells by nigellone. Ann Allergy 1993;70(3):237-42.

  8. Islam SN, Begum P, Ahsan T, et al. Immunosuppressive and cytotoxic properties of Nigella sativa. Phytother Res 2004;18(5):395-8.

  9. Kalus U, Pruss A, Bystron J, et al. Effect of Nigella sativa (black seed) on subjective feeling in patients with allergic diseases. Phytother Res 2003;17(10):1209-14.

  10. Mohamed AM, Metwally NM, Mahmoud SS. Sativa seeds against Schistosoma mansoni different stages.Mem Inst Oswaldo Cruz 2005;100(2):205-11.

  11. Zaoui A, Cherrah Y, Alaoui K, et al. Effects of Nigella sativa fixed oil on blood homeostasis in rat. J Ethnopharmacol 2002;79(1):23-6.

  12. Steinmann A, Schatzle M, Agathos M, Breit R. Allergic contact dermatitis from black cumin (Nigella sativa) oil after topical use. Contact Dermatitis 1997;36(5):268-9.

  13. Zaoui A, Cherrah Y, Mahassini N, et al. Acute and chronic toxicity of Nigella sativa fixed oil. Phytomedicine 2002;9(1):69-74.

  14. Boskabady MH, Javan H, Sajady M, Rakhshandeh H. The possible prophylactic effect of Nigella sativa seed extract in asthmatic patients. Fundam Clin Pharmacol. 2007 Oct;21(5):559-66.

  15. Dehkordi FR, Kamkhah AF. Antihypertensive effect of Nigella sativa seed extract in patients with mild hypertension. Fundam Clin Pharmacol. 2008 Aug;22(4):447-52.

  16. Akhondian J, Kianifar H, Raoofziaee M, et al. The effect of thymoquinone on intractable pediatric seizures (pilot study). Epilepsy Res. 2011 Jan;93(1):39-43.

  17. Al-Jenoobi FI, Al-Thukair AA, Abbas FA, et al. Effect of black seed on dextromethorphan O- and N-demethylation in human liver microsomes and healthy human subjects. Drug Metab Lett. 2010 Jan;4(1):51-5.

  18. Effenberger-Neidnicht K, Schobert R. Combinatorial effects of thymoquinone on the anti-cancer activity of doxorubicin. Cancer Chemother Pharmacol. 2011 Apr;67(4):867-74.

  19. Salem EM, Yar T, Bamosa AO, et al. Comparative study of Nigella Sativa and triple therapy in eradication of Helicobacter Pylori in patients with non-ulcer dyspepsia. Saudi J Gastroenterol. 2010 Jul-Sep;16(3):207-14.

  20. Bamosa AO, Kaatabi H, Lebdaa FM, et al. Effect of Nigella sativa seeds on the glycemic control of patients with type 2 diabetes mellitus. Indian J Physiol Pharmacol. 2010 Oct-Dec;54(4):344-54.

  21. Khader M1, Bresgen N, Eckl PM. In vitro toxicological properties of thymoquinone. Food Chem Toxicol. 2009 Jan;47(1):129-33. doi: 10.1016/j.fct.2008.10.019.

  22. El-Halawany AM, El Dine RS, Chung MH, et al. Screening for estrogenic and antiestrogenic activities of plants growing in Egypt and Thailand. Pharmacognosy Res. 2011 Apr;3(2):107-13. doi: 10.4103/0974-8490.81958.

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