Used for the treatment of tuberculosis, isoniazid can interfere with the absorption or metabolism of numerous nutrients. Since this antibiotic is commonly taken for a very long period of time, deficiencies can mount up over the course of treatment, impairing overall health.
Individuals who take isoniazid may develop nerve problems such as tingling or numbness in the arms, hands, legs, and feet. The cause is believed to be the drug's interference with the action of vitamin B
In fact, use of isoniazid is one cause of the few occasions in which vitamin B
deficiency is seen in the developed world.
To prevent these complications, it may make sense to take vitamin B
supplements at a dose of 15 to 30 mg per day when using isoniazid.
According to animal studies, isoniazid can interfere with the body's ability to produce vitamin B
(niacin) by blocking a key enzyme. This can produce either a subtle or an all-out niacin deficiency (known as pellagra).
Taking niacin supplements at standard U.S. Dietary Reference Intake (formerly known as the Recommended Dietary Allowance) doses should help you get the niacin you need.
This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.
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