The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Common Side Effects
These side effects were reported in at least 2% of people:
- Headache
- Low blood potassium levels
- Diarrhea
- Low blood magnesium levels
- Muscle twitches
- Nausea
Less Common Side Effects
- Fast heart rate
- Blurry vision
- Dry mouth
- Muscle pain
- Nasal congestion
Methylene Blue serious side effects
Contact your healthcare provider immediately if you experience any of the following.
- Serious allergic reaction: hives, rash, blisters, skin reddening, swelling of the lips or tongue, difficulty breathing
- Serotonin syndrome: fast heart rate, dizziness, sweating, flushing, tremor (shakiness), muscle stiffness, muscle twitching or spasms, uncoordinated movement, distress, seizures, distress, hallucinations, coma
- Hemolytic anemia (low red blood cell count): tiredness, dizziness, weakness, high heart rate, yellowing of the skin or eyes, dark-colored urine
Source: DailyMed
The following Methylene Blue side effects have also been reported
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor or nurse immediately if any of the following side effects occur:
Incidence not known
Agitation
bluish-colored lips, fingernails, or palms
confusion
dark urine
difficulty breathing
difficulty swallowing
dizziness or lightheadedness
fast heartbeat
headache
hives or welts, itching, or skin rash
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
overactive reflexes
pale skin
poor coordination
rapid heart rate
redness of the skin
restlessness
shivering
sweating
talking or acting with excitement you cannot control
tightness in the chest
trembling or shaking
twitching
unusual bleeding or bruising
unusual tiredness or weakness
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
Abdominal or stomach pain
bigger, dilated, or enlarged pupils (black part of the eye)
blue staining of the urine, skin, and mucous membranes
bluish-colored lips, fingernails, or palms
blurred vision
burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
confusion
dark urine
difficulty breathing
dizziness or lightheadedness
dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
fear
headache
increased sensitivity of the eyes to light
pale skin
rapid heart rate
rapid shallow breathing
shakiness in the legs, arms, hands, or feet
tightness in the chest
unusual bleeding or bruising
unusual tiredness or weakness
vomiting
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Change in taste
changes in skin color
feeling hot or cold
increased sweating
loss of taste
muscle or joint pain
pain at the infusion site
pain in the arms or legs
Less common
Back pain
bruising
chills
general feeling of discomfort or illness
large, flat, blue or purplish patches in the skin
loss of appetite
muscle aches and pains
trouble sleeping
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
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