home > drugs a-z list > macrodantin (nitrofurantoin macrocystals capsule) drug center > macrodantin (nitrofurantoin macrocystals capsule) drug - consumer side effects and precautions

This medication may cause your urine to turn dark yellow or brown in color. This effect is harmless and will disappear when the medication is stopped.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

This drug may infrequently cause very serious (rarely fatal) lung problems. Lung problems may occur soon after starting the medicine or after long-term use. Seek immediate medical attention if you notice any of the following unlikely but very serious side effects: chest pain, shortness of breath, unusual/persistent cough.

Tell your doctor immediately if any of these rare but very serious side effects occur: new signs of infection (e.g., fever, persistent sore throat), easy bruising/bleeding, mental/mood changes, persistent or severe headaches, vision changes.

This drug may rarely cause serious (possibly fatal) liver disease, blood or nerve problems. Tell your doctor immediately if you notice any of the following rare but very serious side effects: persistent nausea/vomiting, dark urine, yellowing of eyes/skin, unusual/persistent fatigue, fast/pounding heartbeat, numbness/tingling of the arms/legs, muscle weakness.

This medication may rarely cause a severe intestinal condition (Clostridium difficile-associated diarrhea) due to a type of resistant bacteria. This condition may occur during treatment or weeks to months after treatment has stopped. Do not use anti-diarrhea products or narcotic pain medications if you have any of the following symptoms because these products may make them worse. Tell your doctor immediately if you develop: persistent diarrhea, abdominal or stomach pain/cramping, blood/mucus in your stool.

Use of this medication for prolonged or repeated periods may result in oral thrush or a new vaginal yeast infection (e.g., oral or vaginal fungal infection). Contact your doctor if you notice white patches in your mouth, a change in vaginal discharge, or other new symptoms.

A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking nitrofurantoin, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: little or no urine output (oliguria or anuria), severe kidney disease, certain genetic conditions (glucose-6-phosphate dehydrogenase deficiency), a history of liver problems due to nitrofurantoin use in the past.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: certain blood disorders (e.g., anemia), kidney or liver problems, lung diseases, certain nerve problems (peripheral neuropathy), certain eye diseases (optic neuritis), diabetes, untreated mineral imbalance, vitamin B deficiency.

This drug may make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.

Caution is advised when using this drug in the elderly because they may be more sensitive to the side effects of the drug (e.g., lung or liver problems).

This medication should be used only when clearly needed during pregnancy. This medication should not be taken if you are at term (weeks 38-42 of pregnancy), near or at the time of delivery due to possible harm to the newborn, such as a certain blood problem (hemolytic anemia). Discuss the risks and benefits with your doctor.

This medication passes into breast milk and may have undesirable effects on nursing infants less than one month old and infants with a certain genetic condition (G-6-PD deficiency). Consult your doctor before breast-feeding.