Methylene Blue 50mg/10ml Inj, 10ml

Methylene Blue acts as an electron acceptor, converting ferric iron (Fe3+) in methemoglobin back to ferrous iron (Fe2+) in hemoglobin. This process is facilitated by NADPH-dependent methemoglobin reductase (diaphorase 1). Methylene Blue itself is reduced to leucomethylene blue, which then reduces methemoglobin. It also has weak, non-selective monoamine oxidase (MAO) inhibitory properties.

Serious Side Effects: Seek Medical Help Immediately

Although rare, this medication can cause severe and potentially life-threatening side effects. If you experience any of the following symptoms, contact your doctor or seek medical attention right away:

Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of electrolyte problems, including:
+ Mood changes
+ Confusion
+ Muscle pain, cramps, or spasms
+ Weakness
+ Shakiness
+ Change in balance
+ Abnormal heartbeat
+ Seizures
+ Loss of appetite
+ Severe upset stomach or vomiting
Dizziness or fainting
Confusion
Changes in vision
Feeling extremely tired or weak
Pale skin
Dark urine or yellowing of the skin or eyes
Seizures

Other Possible Side Effects

Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms, contact your doctor for advice:

Urine or stool turning blue or green (this is a normal and harmless effect)
Skin turning blue-green
Pain, redness, or swelling at the injection site
Diarrhea or stomach upset
Headache

Reporting Side Effects

This list is not exhaustive, and you may experience other side effects. If you have questions or concerns, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.

Before Taking This Medication: Important Information to Share with Your Doctor

It is essential to inform your doctor about the following:

Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction you experienced.
If you have a condition called G6PD deficiency.
If you are pregnant or think you might be pregnant. This medication may pose a risk to your unborn baby, so it is crucial to discuss the potential benefits and risks with your doctor.
If you are breastfeeding. You should not breastfeed while taking this medication or for 8 days after your last dose.

Additionally, this medication may interact with other drugs or health conditions. Therefore, it is vital to:

Inform your doctor and pharmacist about all the medications you are taking, including prescription and over-the-counter drugs, natural products, and vitamins.
Share information about your health problems, as this will help your doctor determine if it is safe for you to take this medication.
* Never start, stop, or change the dose of any medication without first consulting your doctor to ensure your safety.

It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Regular monitoring is crucial, so be sure to undergo blood work, other laboratory tests, blood pressure checks, and heart rate assessments as directed by your doctor. Additionally, you will need to have your heart rhythm checked with an electrocardiogram (ECG) as instructed.

As this medication may interfere with certain laboratory tests, it is vital to notify all your healthcare providers and laboratory personnel that you are taking this drug. To ensure your safety, avoid operating a vehicle or engaging in activities that require alertness until you are aware of how this medication affects you.

You may be more susceptible to sunburn while taking this medication. To minimize this risk, limit your exposure to the sun, sunlamps, and tanning beds. When going outside, use sunscreen and wear protective clothing and eyewear to safeguard yourself against the sun's harmful effects.

• Serotonergic drugs (e.g., SSRIs, SNRIs, TCAs, MAOIs, triptans, buspirone, tramadol, fentanyl, St. John's Wort) - risk of serotonin syndrome.
• Patients with G6PD deficiency - risk of severe hemolysis.
• Patients with severe renal impairment.

• Other methemoglobin-inducing agents (e.g., dapsone, nitrates, local anesthetics) - may exacerbate methemoglobinemia.
• Drugs that prolong QT interval - theoretical risk of additive QT prolongation.
• Phenothiazines (e.g., chlorpromazine) - may increase risk of extrapyramidal symptoms.

• Anticoagulants (e.g., warfarin) - Methylene Blue may interfere with laboratory tests (e.g., INR) or have theoretical additive anticoagulant effects.
• Antimalarials (e.g., primaquine, chloroquine) - increased risk of hemolysis in G6PD deficient individuals.

• None specifically identified as minor with clinical significance.

• Cyanosis (especially unresponsive to oxygen)
• Dyspnea
• Headache
• Dizziness
• Fatigue
• Nausea/vomiting
• Confusion
• Altered mental status
• Chest pain
• Arrhythmias
• Seizures
• Signs of serotonin syndrome (agitation, hyperthermia, tremor, hyperreflexia, myoclonus, diaphoresis)

Generally not recommended during pregnancy unless the benefits clearly outweigh the risks. Methylene Blue has been associated with fetal toxicity (e.g., hemolytic anemia, hyperbilirubinemia) in some animal and human cases. The FDA has removed pregnancy categories, but historically it was considered Category D or X by some sources.

Methylene Blue is excreted into breast milk and can cause hemolytic anemia in G6PD deficient infants. Breastfeeding is generally not recommended during treatment and for several days (e.g., up to 8 days) after the last dose. Consult with a healthcare provider.

Dosing is weight-based. Neonates and infants may be more susceptible to adverse effects, particularly hemolysis, due to immature enzyme systems. G6PD deficiency screening is crucial in this population.

Use with caution due to potential for age-related decline in renal function and increased susceptibility to adverse effects. Start with lower doses and monitor closely.

• Methylene Blue itself can cause a dose-dependent methemoglobinemia at very high doses (e.g., >7 mg/kg), as it can oxidize hemoglobin directly.
• The blue discoloration of urine and skin is a normal and expected side effect, not a sign of toxicity.
• Pulse oximetry readings can be falsely low or inaccurate in the presence of methemoglobinemia and after Methylene Blue administration. Co-oximetry is required for accurate methemoglobin level measurement.
• Always check for G6PD deficiency before administration, if possible. If G6PD deficiency is suspected or confirmed, Methylene Blue is contraindicated, and alternative treatments (e.g., exchange transfusion, hyperbaric oxygen) should be considered for severe methemoglobinemia.
• Be vigilant for signs of serotonin syndrome, especially if the patient is on other serotonergic medications. Methylene Blue is a potent, non-selective MAO inhibitor at therapeutic doses for methemoglobinemia.

• Supportive care (e.g., oxygen therapy)
• Exchange transfusion (for severe methemoglobinemia, especially in G6PD deficiency or Methylene Blue failure)
• Hyperbaric oxygen (adjunctive therapy in severe cases)
• Ascorbic acid (Vitamin C) - less effective and slower acting, generally reserved for mild cases or as an adjunct.

If your symptoms or health problems do not improve or worsen over time, it is essential to contact your doctor for further guidance. To ensure safe use, never share your medication with others or take someone else's medication. Store all medications in a secure location, out of reach of children and pets, to prevent accidental ingestion.

Proper disposal of unused or expired medications is crucial. Do not dispose of them by flushing down the toilet or pouring down the drain unless specifically instructed to do so. If you are unsure about the best method for disposing of your medication, consult your pharmacist for advice. Many communities have drug take-back programs that provide a safe and environmentally friendly way to dispose of unwanted medications.

Some medications may come with an additional patient information leaflet. Check with your pharmacist to see if this applies to your prescription. If you have any questions or concerns about your medication, do not hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider for guidance.

In the event of a suspected overdose, immediately contact your local poison control center or seek emergency medical attention. Be prepared to provide information about the medication taken, the amount, and the time it was taken, as this will aid in providing appropriate treatment.