Nitrofurantoin (Macrobid) is an antibiotic used to treat or prevent a urinary tract infection (UTI). Some side effects include nausea, headache, and gas. It can also make your urine turn dark yellow or brown. Nitrofurantoin (Macrobid) doesn't have many interactions with other medications. There's a lower-cost generic version of nitrofurantoin (Macrobid) available.
Nitrofurantoin (Macrobid) is a nitrofuran antibiotic. The medication collects in your urine. It kills bacteria in the urinary tract by damaging or blocking proteins the bacteria need to survive.
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.
Contact your healthcare provider immediately if you experience any of the following.
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 immediately if any of the following side effects occur:
More common
Changes in facial skin color
chills
general feeling of discomfort or illness
hoarseness
joint or muscle pain
shortness of breath
skin rash
sudden trouble in swallowing or breathing
swelling of the face, mouth, hands, or feet
troubled breathing
Less common
Black, tarry stools
blood in the urine or stools
burning, numbness, tingling, or painful sensations
dizziness
drowsiness
headache
pinpoint red spots on the skin
unsteadiness or awkwardness
unusual bleeding or bruising
unusual tiredness or weakness
weakness in the arms, hands, legs, or feet
Rare
Abdominal or stomach pain
blindness
blistering, peeling, or loosening of the skin and mucous membranes
blue-yellow color blindness
bluish color of the fingernails, lips, skin, palms, or nail beds
blurred vision or loss of vision, with or without eye pain
bulging soft spot on the head of an infant
change in the ability to see colors, especially blue or yellow
confusion
cracks in the skin
darkening of the urine
decreased vision
diarrhea, watery and severe, which may also be bloody
general tiredness and weakness
light-colored stools
loss of appetite
loss of heat from the body
mental depression
mood or mental changes
nausea or vomiting
pale skin
pale stools
red skin lesions, often with a purple center
red, irritated eyes
red, swollen skin
red, thickened, or scaly skin
skin rash
sores, ulcers, or white spots on the lips or in the mouth
swollen or painful glands
tenderness of salivary glands
unpleasant breath odor
upper right abdominal pain
visual changes
vomiting of blood
wheezing or tightness in the chest
yellow eyes or skin
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:
Incidence not known
Dizziness or lightheadedness
feeling of constant movement of self or surroundings
lack or loss of strength
loss of hair, temporary
sensation of spinning
uncontrolled eye movements
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.
Nitrofurantoin (Macrobid) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
In some rare cases, nitrofurantoin (Macrobid) can damage your lungs. Your risk is higher if you're taking this medication for more than 6 months. Talk to your healthcare provider as soon as possible if you're having difficulty breathing or have a new cough that doesn't go away.
Very rarely, some people taking nitrofurantoin (Macrobid) have had severe or life-threatening liver damage. Your risk might be higher if you have or have had liver problems. If you experience unexplained stomach pain, nausea, vomiting, dark urine, pale stools, or yellowing of your skin or whites of your eyes, contact your healthcare provider right away. You'll likely need to get blood tests done so your provider can check your liver health.
Nitrofurantoin (Macrobid) can damage the nerves in your arms, legs, and rarely eyes. This effect isn't very common, but certain medical conditions, including kidney problems, can raise your risk of this happening. In some cases, the damage is permanent. Tell your healthcare provider if you experience numbness, tingling, or a prickling sensation in any part of your body while using this medication. If you're taking nitrofurantoin (Macrobid) for a long period of time, you'll likely need to get blood tests done regularly so your provider can check your kidney function and risk of nerve damage.
Nitrofurantoin (Macrobid) can damage your red blood cells and cause hemolytic anemia. Your risk is higher if you're lacking a specific protein in your body called glucose-6-phosphate dehydrogenase (G6PD). Black people and those of Mediterranean or Middle Eastern ethnicity are more likely to have this deficiency. Tell your healthcare provider about the medical conditions you have before starting this antibiotic. Let your provider know if you feel unexplainably weak, dizzy, or tired while taking nitrofurantoin (Macrobid).
Like all antibiotics, nitrofurantoin (Macrobid) can cause diarrhea. This is because nitrofurantoin (Macrobid) can change the amount of "good" bacteria that's normally in your gut, which affects how well they keep dangerous bacteria away. In rare cases, this diarrhea is caused by an overgrowth of bacteria called Clostridioides difficile (commonly called C. diff). C. diff-related diarrhea is very contagious and can lead to life-threatening dehydration. If you experience watery or bloody stools, stomach cramps, or fever, contact your provider right away. If you have C. diff, be sure to wash your hands with soap for 20 seconds often, and try to use a different bathroom from anyone living with you until you're better.
Treatment of UTI
Prevention of UTI
GoodRx has partnered with to provide reviews on the different aspects of Nitrofurantoin (Macrobid).
Learn more about the effectiveness of Nitrofurantoin (Macrobid) based on real life experiences.
Based on 13 people taking this medication
4.7
4.5
5.0
Severity of side effects
Based on 80 people taking this medication
0%
50%
100%
Diarrhea
3%
Abdominal cramps
2%
Nausea
2%
Tiredness
2%
Thrush
2%
Reasons people stopped taking Nitrofurantoin (Macrobid)
Based on 122 people who have taken this medication
Course of treatment ended
65%
Doctor's advice
19%
Other
8%
Did not seem to work
5%
Side effects too severe
5%
Personal research
2%
How long people take Nitrofurantoin (Macrobid)
Based on 107 people who have taken this medication
0%
50%
100%
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because Nitrofurantoin (Macrobid) will not be safe for you to take.