Antelaea azadirachta, Arishta, Arishtha, Azadirachta indica, Bead Tree, Holy Tree, Huile de Neem, Indian Lilac, Indian Neem, Lilas des Indes, Lilas de Perse, Margosa, Margosa Tree, Margousier, Margousier à Feuilles de Frêne, Margousier d'Inde, Melia azadirachta, Neem Oil, Neem Tree, Melia azadirachta, Nim, Nimb, Nimba, Persian Lilac, Pride of China.


Overview Information

Neem is a tree. It grows in tropical regions such as India and Myanmar. The bark, leaves, and seeds are used to make medicine. Less often, the root, flower, and fruit are also used.

Neem is used for tooth plaque, gum disease (gingivitis), lice, to repel insects, and for other conditions, but there is no good scientific evidence to support most of these uses.

How does it work?

Neem contains chemicals that might help reduce blood sugar levels, heal ulcers in the digestive tract, prevent pregnancy, kill bacteria, and prevent plaque formation in the mouth.


Uses & Effectiveness?

Possibly Effective for

  • Tooth plaque. Most research shows that applying a gel containing neem leaf extract to the teeth or using a neem mouthwash can reduce the amount of plaque on the teeth. But it might not be as helpful as using chlorhexidine mouthwash.
  • A mild form of gum disease (gingivitis). Most research shows that applying a gel containing neem leaf extract or using a neem mouthwash can reduce gingivitis in some people, but it doesn't seem to be as helpful as chlorhexidine mouthwash and it may not be effective for people with long-standing gingivitis.
  • Lice. Clinical research shows that applying a neem extract shampoo to the scalp once completely cures head lice in children.

Insufficient Evidence for

More evidence is needed to rate the effectiveness of neem for these uses.

Side Effects

Side Effects & Safety

When taken by mouth: Neem bark extract is POSSIBLY SAFE for most adults when taken by mouth, short-term. Doses of up to 60 mg daily for up to 10 weeks have been safely used in humans. Neem is POSSIBLY UNSAFE when taken by mouth in large doses or for long periods of time. It might harm the kidneys and liver.

When applied to the skin: Neem leaf extract gel is POSSIBLY SAFE when applied inside the mouth for up to 6 weeks. Neem oil or cream is POSSIBLY SAFE when applied to the skin for up to 2 weeks.

Special Precautions & Warnings:

Pregnancy: Neem oil and neem bark are LIKELY UNSAFE when taken by mouth during pregnancy. They can cause a miscarriage.

Breast-feeding: There isn't enough reliable information to know if neem is safe to use when breast-feeding. Stay on the safe side and avoid use.

Children: Neem extract shampoo is POSSIBLY SAFE in children when applied once or twice to the head for 10 minutes, then rinsed with warm water. Neem seeds and seed oil are LIKELY UNSAFE when taken by mouth in children. Serious side effects in infants and small children can happen within hours after taking neem oil. These serious side effects include vomiting, diarrhea, drowsiness, blood disorders, seizures, loss of consciousness, coma, brain disorders, and death.

"Auto-immune diseases" such as multiple sclerosis (MS), lupus (systemic lupus erythematosus, SLE), rheumatoid arthritis (RA), or other conditions: Neem might cause the immune system to become more active. This could increase the symptoms of auto-immune diseases. If you have one of these conditions, it's best to avoid using neem.

Diabetes: There is some evidence that neem can lower blood sugar levels and might cause blood sugar to go too low. If you have diabetes and use neem, monitor your blood sugar carefully. It might be necessary to change the dose of your diabetes medication.

Reduced ability to have children (infertility): There is some evidence that neem can harm sperm. It might also reduce fertility in other ways. If you are trying to have children, avoid using neem.

Organ transplant: There is a concern that neem might decrease the effectiveness of medications that are used to prevent organ rejection. Do not use neem if you have had an organ transplant.

Surgery: Neem might lower blood sugar levels. There is a concern that it might interfere with blood sugar control during and after surgery. Stop using neem at least 2 weeks before a scheduled surgery.



Moderate Interaction

Be cautious with this combination

  • Lithium interacts with NEEM

    Neem might have an effect like a water pill or "diuretic." Taking neem might decrease how well the body gets rid of lithium. This could increase how much lithium is in the body and result in serious side effects. Talk with your healthcare provider before using this product if you are taking lithium. Your lithium dose might need to be changed.

  • Medications for diabetes (Antidiabetes drugs) interacts with NEEM

    Neem might decrease blood sugar. Diabetes medications are also used to lower blood sugar. Taking neem along with diabetes medications might cause your blood sugar to go too low. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.

    Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.

  • Medications that decrease the immune system (Immunosuppressants) interacts with NEEM

    Neem might increase the immune system. By increasing the immune system, neem might decrease the effectiveness of medications that decrease the immune system.

    Some medications that decrease the immune system include azathioprine (Imuran), basiliximab (Simulect), cyclosporine (Neoral, Sandimmune), daclizumab (Zenapax), muromonab-CD3 (OKT3, Orthoclone OKT3), mycophenolate (CellCept), tacrolimus (FK506, Prograf), sirolimus (Rapamune), prednisone (Deltasone, Orasone), corticosteroids (glucocorticoids), and others.



The following doses have been studied in scientific research:



  • For a mild form of gum disease (gingivitis): A neem leaf extract gel has been applied to the teeth and gums twice daily for 6 weeks. 15 mL of 2% neem solution used as a mouthwash for 30 seconds after brushing daily for 3 weeks.
  • For tooth plaque: A neem leaf extract gel has been applied to the teeth and gums twice daily for 6 weeks. 15 mL of 2% neem solution used as a mouthwash for 30 seconds after brushing daily for 3 weeks. 5 mL of neem solution used as a mouthwash twice daily for 30 days.

  • For lice: 100 mL of a specific neem extract shampoo (Licener, Pronovo Laboratories) applied to dry hair for 10 minutes then rinsed with warm water once or repeated for a second application.

View References


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  • Bandyopadhyay U, Biswas K, Sengupta A, et al. Clinical studies on the effect of Neem (Azadirachta indica) bark extract on gastric secretion and gastroduodenal ulcer. Life Sci 2004;75:2867-78. View abstract.
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CONDITIONS OF USE AND IMPORTANT INFORMATION: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

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