Toxicity
Studies done when Azadirachtin (the primary active pesticidal ingredient in neem oil) was approved as a pesticide showed that when neem leaves were fed to male albino rats for 11 weeks, 100% (reversible) infertility resulted.
Neem oil and other neem products such as neem leaves and neem tea should not be consumed by pregnant women, women trying to conceive, or children.
There is some evidence that internal medicinal use may be associated with liver damage in children.
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