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Methylene blue (injection)

Generic name: methylene blue (injection) [ METH-i-leen-BLOO ]
Brand names: Provayblue, Urolene Blue
Dosage forms: injectable solution (10 mg/mL), intravenous solution (5 mg/mL)
Drug classes: Antidotes, Miscellaneous diagnostic dyes

Medically reviewed by Drugs.com on Jul 3, 2023. Written by Cerner Multum.

What is methylene blue?

Methemoglobin is a form of hemoglobin (HEEM o glo bin). Hemoglobin is a substance in blood that carries oxygen and distributes it to your tissues and organs. However, methemoglobin is not a type of hemoglobin that is useful in carrying oxygen.

Methemoglobin normally exists in small amounts in the blood. However, when methemoglobin levels increase, the blood is less efficient in circulating oxygen. The resulting lack of oxygen throughout the body can cause symptoms such as pale or blue-colored skin.

Methemoglobinemia is a condition in which methemoglobin is present in high levels in the blood. Methemoglobinemia can occur when a person is exposed to certain drugs or chemicals such as nitrites.

Methylene blue injection is used to treat methemoglobinemia. methylene blue works by converting methemoglobin to a more efficient type of hemoglobin to better carry oxygen throughout the body.

Methylene blue may also be used for purposes not listed in this medication guide.

Methylene blue side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Tell your caregivers right away if you have:

Common side effects of methylene blue may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Warnings

You should not be treated with methylene blue if you have glucose-6-phosphate dehydrogenase (G6PD) deficiency.

Many drugs can interact with methylene blue. Tell your doctor about all your current medicines and any you recently stopped using, especially an antidepressant.

Before taking this medicine

You should not be treated with methylene blue if you are allergic to it, or if you have:

Many drugs can interact with methylene blue. Tell your doctor about all your current medicines and any you recently stopped using, especially:

To make sure methylene blue is safe for you, tell your doctor if you have:

Using methylene blue during pregnancy could harm the unborn baby. Tell your doctor if you are pregnant.

Do not breast-feed within 8 days after you received methylene blue. If you use a breast pump during this time, throw out any milk you collect. Do not feed it to your baby.

How is methylene blue given?

Methylene blue is injected into a vein through an IV. A healthcare provider will give you this injection. The IV infusion can take up to 30 minutes to complete.

Your breathing, blood pressure, oxygen levels, kidney function, and other vital signs will be watched closely while you are receiving methylene blue. Your blood will also need to be tested to help your doctor determine that the medicine is working.

You may only need to receive one dose of methylene blue. If you do need a second dose, it can be given 1 hour after your first dose.

Methylene blue will most likely cause your urine or stools to appear blue or green in color. This is a normal side effect of the medication and will not cause any harm. However, this effect may cause unusual results with certain urine tests.

What happens if I miss a dose?

Because you will receive methylene blue in a clinical setting, you are not likely to miss a dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include vomiting, stomach pain, chest pain or tightness, wheezing, trouble breathing, feeling like you might pass out, fast heart rate, anxiety, confusion, tremor, dilated pupils, blue-colored skin or lips, numbness, or tingling.

What should I avoid while receiving methylene blue?

methylene blue may cause blurred vision and may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly.

For at least 24 hours after treatment with methylene blue, avoid exposure to sunlight or tanning beds. This medicine can make you sunburn more easily. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

What other drugs will affect methylene blue?

Many drugs can interact with methylene blue, and some drugs should not be used together. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide. Tell your doctor about all medicines you use, and those you have recently used before your treatment with methylene blue.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.