Overview

Methylene blue is a blue dye made in a lab. It is a prescription medication given in hospitals. Some people take methylene blue by mouth as a supplement.

Methylene blue might change the messaging inside cells. This might help with memory and brain function. It might also slow down aging and inflammation.

People sometimes use methylene blue to improve memory and thinking skills (cognitive function) and for aging, depression, malaria, and many other conditions, but there is no good scientific evidence to support these uses. There is also no good evidence to support using methylene blue for COVID-19.

Methylene blue is approved by the U.S. FDA as a prescription drug that is injected. It is given to people with high levels of a chemical called methemoglobin in the blood (methemoglobinemia). It is also given in the hospital for other conditions. These uses aren't covered in this topic. People take methylene blue supplements by mouth.



Uses & Effectiveness

Effective for

<p>None</p>

Likely Effective for

<p>None</p>

Possibly Effective for

<p>None</p>

Possibly Ineffective for

<p>None</p>

Likely InEffective for

<p>None</p>

Insufficient Evidence for

<p>None</p>

Side Effects

When taken by mouth: There isn't enough reliable information to know if methylene blue is safe. Methylene blue can cause some side effects, such as blue urine, diarrhea, headache, nausea, and vomiting.

Special Precautions and Warnings

When taken by mouth: There isn't enough reliable information to know if methylene blue is safe. Methylene blue can cause some side effects, such as blue urine, diarrhea, headache, nausea, and vomiting.

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

Children: There isn't enough reliable information to know if methylene blue is safe. Stay on the safe side and avoid use.

An inherited disorder that causes red blood cells to break down in response to stress (G6PD deficiency): Methylene blue might cause dangerous side effects. Avoid use.

Kidney disease: Methylene blue might stay in the body longer and cause dangerous side effects.

Liver disease: Methylene blue might stay in the body longer and cause dangerous side effects.

Surgery: Methylene blue might affect serotonin levels in the brain, interfering with medications used during surgery. Stop using methylene blue at least two weeks before a scheduled surgery.

Interactions

    Moderate Interaction

    Be cautious with this combination

  • Drying medications (Anticholinergic drugs) interacts with Methylene Blue

    Taking methylene blue and drying medications together might cause side effects including dizziness, dry skin, fast heartbeat, low blood pressure, and other serious side effects.

    Some of these drying medications include atropine, scopolamine, and some medications used for allergies (antihistamines), and for depression (antidepressants).

  • Serotonergic drugs interacts with Methylene Blue

    Methylene blue might increase a brain chemical called serotonin. Some medications also have this effect. Taking methylene blue along with these medications might increase serotonin too much. This might cause serious side effects including heart problems, seizures, and vomiting.

Dosing

There isn't enough reliable information to know what an appropriate dose of methylene blue might be. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult a healthcare professional before using.
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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.

This copyrighted material is licensed from Therapeutic Research Center, LLC. Information from this source is evidence-based and objective, and without commercial influence. For professional medical information on natural medicines, see Natural Medicines Comprehensive Database Professional Version.
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