What Is Neem?

Neem capsules, powder, tincture, oil, and creams

Verywell / Anastasia Tretiak 

Neem (Azadirachta indica) is a type of tree used in alternative medicine to treat or prevent certain health problems. Some people believed that it can reduce pain, preserve eyesight, boost the immune system, and protect against heart or liver disease.

Neem is available as a capsule, powder, oil, tincture, cream, or mouthwash. Neem oil can be used on the skin to treat conditions like dandruff and acne, while neem leaf extract can be taken by mouth to treat stomach ulcers and dental problems. Some remedies are made from the bark, flowers, or fruit of the neem tree.

Also Known As

  • Arishta
  • Bead Tree
  • Holy Tree
  • Indian Lilac
  • Persian Lilac
  • Pride of China

What Is Neem Used For?

Neem is used in an ancient form of healing, called Ayurveda, to treat asthma, constipation, cough, diabetes, stomach ulcers, indigestion, gum disease, urinary tract infection, and other illnesses.

Although neem has not been studied extensively, several small studies suggest that it may have some potential health benefits.

Dental Health

Several studies suggest that neem can help fight the buildup of plaque on teeth and prevent a type of gum disease called gingivitis.

A 2017 study in the Journal of Contemporary Dental Practices reported that neem mouthwash was as effective as commercial mouthwashes containing chlorhexidine gluconate, a substance commonly used to prevent gum disease. However, the study was small, involving only 40 people for a period of one week.

A larger review of studies published in the International Journal of Dental Hygiene did not reach the same conclusions. The researchers could find no evidence that neem mouthwash was a reasonable alternative for a chlorhexidine mouthwash.

Dandruff

Neem oil is sometimes used to treat dandruff, although no one knows precisely how it works. The oil is thought to reduce the inflammation that contributes to redness, itching, and flaking. Neem may also help fight the fungus that is another possible cause of dandruff. 

There is some evidence to support these claims. Lab studies have found that neem contains a substance called nimbin that is anti-inflammatory. Other studies have isolated a plant-based chemical called quercetin that has strong antifungal and antibacterial effects.

Acne

Neem oil may also help treat acne and other skin conditions due to its anti-inflammatory and antibacterial properties. 

A study published in the Journal of Acute Diseases in 2013 reported that neem oil was able to kill many types of acne-causing bacteria. It did so without the skin irritation or dryness that other acne medications can cause. This suggests that neem oil may be an option for the long-term treatment of mild acne.

Stomach Ulcers

Neem shows promise in the treatment of peptic ulcers, according to a 2009 study in Phytotherapy Research. Peptic ulcers, also known as stomach ulcers, can cause stomach pain and other symptoms due to the production of too much stomach acid. The study suggests that neem bark extract can partially block the secretion of this acid and help reduce symptoms.

Another study published in the Journal of Ethnopharmacology in 2019 reported that neem oil was able to kill Helicobacter pylori (H. pylori) in test tubes. H. pylori is a type of bacteria that is the major cause of peptic ulcers.

Safety Warning

Although there is evidence that neem oil can kill H. pylori in test tubes, drinking neem oil is not advised. Doing so can lead to neem oil poisoning and cause symptoms like nausea, vomiting, and seizures.

Possible Side Effects

Neem supplements are generally safe for use in adults when taken by mouth for a short period of time. Doses of up to 60 milligrams (mg) per day have been used safely for up to 10 weeks in clinical trials.

Little is known about the long-term safety of neem supplements. There is some concern that neem may cause damage to the kidneys and liver, particularly if overused. Some studies suggest that it may lower the sperm count.

Neem supplements should not be used in children or people who are pregnant or breastfeeding due to the lack of safety research in those groups. Some early studies suggested that taking high-concentration extracts in pregnancy may induce labor, although this has not been proven. Even so, it is best to avoid neem just in case.

Neem creams are considered safe for use on the skin. Neem oil can also be used but needs to be diluted with a neutral carrier oil, like almond oil, to avoid irritation. Neem oil should not be taken internally.

Neem supplements are only intended for short-term use. Before starting any supplement, speak with your doctor to ensure that it's safe for you to take and doesn't interact with any medications you are taking.

Drug Interactions

There are several possible drug interactions to watch out for if you plan to take a neem supplement. Taking neem with certain medications may reduce the other drug's effectiveness or increase the risk of side effects.

Possible interactions include:

Neem powder
Verywell / Anastasia Tretiak

Selection, Preparation, & Storage

Neem can be found online and in many dietary supplements and natural food stores. It comes in many forms, including capsules, tinctures, powders, oil, creams, shampoos, and mouthwashes.

There are no guidelines for the appropriate use of neem in any form. To ensure safety, follow the instructions on the product label.

Dietary supplements like neem are not strictly regulated by the Food and Drug Administration (FDA). Because of this, the purity and safety of a supplement can vary from one manufacturer to the next.

How to Choose Supplements

To ensure safety, choose supplements that are submitted for evaluation by an independent certifying body like U.S. Pharmacopeia (USF), NSF International, or ConsumerLab. The certification confirms that the product is pure and contains the ingredients listed on the product label.

Summary

Neem has been traditionally used to treat a wide range of health conditions, from skin problems to stomach ulcers, but most of the claims aren't backed by strong science. If you do decide to use neem for any reason, speak with your doctor.

This is especially true if you have a chronic health condition like diabetes, liver, or kidney disease, or are pregnant or breastfeeding. Herbal supplements aren't strictly regulated in the United States, and the long-term safety of products like neem is unknown. Neem should not be used in children.

Frequently Asked Questions

  • Is neem an effective insect repellant?

    Neem oil appears to works similarly to citronella. A 2015 study in Malaria Journal found a 20% neem formula is more than 70% effective against mosquitos for three hours. However, neem was not as effective as DEET in repelling mosquitos.

  • Does neem oil kill lice?

    Yes. There are several anti-lice shampoos on the market that contain neem oil. One study published in 2011 found that a 10-minute treatment with a neem-based product sufficiently killed lice and their eggs.

  • Should I stop neem before surgery?

    Yes. Because neem can reduce blood sugar, it is best to stop taking neem supplements at least two weeks before a scheduled surgery.

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19 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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