Neem

Related Terms

6-desacetyllnimbinene, Azadirachta indica, Azadirachta indica ADR, Azadirachta indica A. juss, azadirachtin, azadirachtin A, azadirachtin H, azadirachtin I, bead tree, beta-sitosterol, BioneemT, dogonyaro, holy tree, immobile, Indian lilac, isomeldenin, limonoids, kohomba oil, margosa, margosa oil, Meliaceae (family), NeemixT, neem flowers, neem-based pesticide, neem kernel powder (NP), neem leaf alcoholic extract (NLE), neem oil, neem seed kernel, neem seed oil, Nim, NIM-76, nimba, nimbandiol, nimbin, nimbinene, nimocinol, Persian lilac, Praneem polyherbal cream, Pride of China, quercetin, village of pharmacy.

Background

Neem is thought to come from northeast India and Myanmar. It has been used to treat infections, skin conditions, and swellings. Neem is also used as a pesticide to protect food and other products from insects. Neem leaves and seed oil are believed to benefit the skin and hair.
Neem extracts often have a strong, overpowering smell similar to that of garlic.
Neem may help reduce plaque in the mouth, repel mosquitoes, treat psoriasis (a skin condition that causes redness and irritation), and help heal ulcers in the stomach and intestines. However, there is a lack of evidence to support these uses at this time.

Evidence Table

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *


Early research suggests that neem may help slow the progression of HIV/AIDS. Further high-quality studies are needed in this area.

C


Early research suggests that neem may help slow the progression of HIV/AIDS. Further high-quality studies are needed in this area.

C


Early studies have found that neem may have protective effects against flies. More research is needed to make a firm conclusion.

C


Early studies have found that neem may have protective effects against flies. More research is needed to make a firm conclusion.

C


Neem seed extract in shampoo has been found to be effective for treating head lice. Further high-quality studies are needed.

C


Neem seed extract in shampoo has been found to be effective for treating head lice. Further high-quality studies are needed.

C


Neem oil and neem cream may protect against mosquito bites. Further research is needed before a firm conclusion can be made on the use of neem as a mosquito repellent.

 C


Neem oil and neem cream may protect against mosquito bites. Further research is needed before a firm conclusion can be made on the use of neem as a mosquito repellent.

 C


Neem may help reduce germs and plaque in the mouth. The effects of neem have been compared to those of chlorhexidine, a prescription drug used to treat gum disease. Further study is needed in this area to make a firm conclusion.

C


Neem may help reduce germs and plaque in the mouth. The effects of neem have been compared to those of chlorhexidine, a prescription drug used to treat gum disease. Further study is needed in this area to make a firm conclusion.

C


Neem has been studied for psoriasis, with limited information available. There is a lack of evidence at this time to support the use of neem for this condition.

 C


Neem has been studied for psoriasis, with limited information available. There is a lack of evidence at this time to support the use of neem for this condition.

 C


Neem has been found to have protective, healing effects on ulcers of the stomach and intestines. However, research is still needed to compare the effects of neem to those of standard treatments.

 C


Neem has been found to have protective, healing effects on ulcers of the stomach and intestines. However, research is still needed to compare the effects of neem to those of standard treatments.

 C
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory

The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

Dosing

Adults (18 years and older)
For ulcers of the stomach and intestines, neem bark extract has been taken by mouth in doses of 30-60 milligrams twice daily for 10 weeks.
For dental plaque, a gel containing neem extract has been applied to the teeth and gums twice a day, before bed and after breakfast, for six weeks. A neem extract mouthwash has been rinsed in the mouth for one minute, twice daily for two weeks, 30 minutes after brushing the teeth. Toothbrushes have been soaked for 12 hours in a 3 percent neem solution before brushing the teeth.
As an insect repellent, 3 milliliters of diluted neem root or leaf extracts has been applied to the skin for two days.
As a mosquito repellent, neem cream (5 percent neem oil in vanishing cream base) has been applied to the skin. Doses of 3-5 milliliters of 0.5-2 percent neem oil have been applied to the skin for up to 12 nights.
For psoriasis, neem capsules have been taken by mouth three times daily after applying crude coal tar and salicylic acid, taking a bath, and having 15 minutes of sun exposure, for 12 weeks.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Interactions

Interactions with Drugs
Neem may lower blood sugar levels. Caution is advised when using medications that may also lower blood sugar. People taking drugs for diabetes by mouth or insulin should be monitored closely by a qualified healthcare professional, including a pharmacist. Medication adjustments may be necessary.
Neem may cause low blood pressure. Caution is advised in people taking drugs that lower blood pressure.
Neem may interfere with the way the body processes certain drugs using the liver's "cytochrome P450" enzyme system. As a result, the levels of these drugs may be altered in the blood, and may cause altered effects or potentially serious adverse reactions. People using any medications should check the package insert, and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.
Neem may also interact with acetaminophen, agents for the blood, agents for the heart, agents for the lungs, agents for the nervous system, agents for the skin, agents for the stomach and intestines, agents that are toxic to the liver, agents that cause abortion, antibiotics, anticancer agents, antiprotozoal agents, antiseptic agents, anti-ulcer agents, antiviral agents, birth control, cyclophosphamide and mitomycin C, fertility agents, heart rate-regulating agents, hormonal agents, insect repellants, morphine, quinine, and thyroid hormones.

Attribution

This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

Anyaehie UB. Medicinal properties of fractionated acetone/water neem [Azadirachta indica] leaf extract from Nigeria: a review. Niger.J Physiol Sci. 2009;24(2):157-159.
Bhaskar MV, Pramod SJ, Jeevika MU, et al. MR imaging findings of neem oil poisoning. AJNR Am J Neuroradiol. 2010;31(7):E60-E61.
Greenblatt DT, Banerjee P, and White JM. Allergic contact dermatitis caused by neem oil. Contact Dermatitis 2012;67(4):242-243.
Iyyadurai R, Surekha V, Sathyendra S, et al. Azadirachtin poisoning: a case report. Clin Toxicol.(Phila) 2010;48(8):857-858.
Kumar V, Singh AP, Meher R, et al. Primary tuberculosis of oral cavity: a rare entity revisited. Indian J Pediatr. 2011;78(3):354-356.
Lee G, Anand SC, and Rajendran S. Are biopolymers potential deodourising agents in wound management? J Wound.Care 2009;18(7):290, 292-290, 295.
Parlani S, Tripathi A, and Singh SV. Increasing the prosthodontic awareness of an aging Indian rural population. Indian J Dent.Res 2011;22(3):367-370.
Paul R, Prasad M, and Sah NK. Anticancer biology of Azadirachta indica L (neem): a mini review. Cancer Biol Ther 9-15-2011;12(6):467-476.
Rasheed A, Avinash Kumar Reddy G, Mohanalakshmi S, et al. Formulation and comparative evaluation of poly herbal anti-acne face wash gels. Pharm.Biol 2011;49(8):771-774.
Sam-Wobo SO, Adeleke MA, Mafiana CF, et al. Comparative repellent activities of some plant extracts against Simulium damnosum complex. Vector.Borne.Zoonotic.Dis. 2011;11(8):1201-1204.
Sam-Wobo SO, Adeleke MA, Mafiana CF, et al. Comparative repellent activities of some plant extracts against Simulium damnosum complex. Vector.Borne.Zoonotic.Dis. 2011;11(8):1201-1204.
Schmahl G, Al-Rasheid KA, Abdel-Ghaffar F, et al. The efficacy of neem seed extracts (Tre-san, MiteStop on a broad spectrum of pests and parasites. Parasitol.Res 2010;107(2):261-269.
Senanayake MP, Rupasinghe S, and Dissanayake PV. Margosa (Kohomba) oil induced toxic encephalopathy following home remedy for intestinal worms. Ceylon Med.J 2009;54(4):140.
Singh SK, Bimal S, Narayan S, et al. Leishmania donovani: assessment of leishmanicidal effects of herbal extracts obtained from plants in the visceral leishmaniasis endemic area of Bihar, India. Exp.Parasitol. 2011;127(2):552-558.
Yamasaki S, Asakura M, Neogi SB, et al. Inhibition of virulence potential of Vibrio cholerae by natural compounds. Indian J Med.Res 2011;133:232-239.