Along with its needing effects, a drug 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 family doctor immediately if any of the following side effects was happen
More common
Changes in facial skin color; chest pain; chills; cough; fever; general feeling of discomfort or illness; hives; hoarseness; itching; joint or muscle pain; shortness of breath; skin rash; sudden trouble in swallowing or breathing; swelling of face, mouth, hands, or feet; troubled breathing
Less common
Black, tarry stools; blood in urine or stools; burning, numbness, tingling, or painful sensations; dizziness; drowsiness; headache; pinpoint red spots on skin; sore throat; unusual bleeding or bruising; unusual tiredness or weakness; weakness in arms, hands, legs, or feet
Rare
Abdominal or stomach pain; blistering, peeling, or loosening of skin and mucous membranes; bluish color of skin; blurred vision or loss of vision, with or without eye pain; bulging fontanel in infants; confusion; darkening of urine; diarrhea, watery and severe, which may also be bloody; loss of appetite; mental depression; mood or mental changes; nausea or vomiting; pale skin; pale stools; red skin lesions, often with a purple center; red, thickened, or scaly skin; skin rash; sores, ulcers, or white spots on lips or in mouth; swollen or painful glands; unpleasant breath odor; visual changes; vomiting of blood; wheezing or tightness in chest; yellow eyes or skin
More common side effects may occur that usually don't needed medical attention. These side effects may go away during treat as your body adjusts to the drug. However, check with your family doctor if any of the following side effects continue or are bothersome:
More common
Diarrhea; gas
After you stop using this drug, your body may need time to adjust. The length of time this takes depends on the amount of drug you were using and how long you using it. During this period of time check with your family doctor immediately if you notice any of the following side effects:
Abdominal or stomach cramps or pain, severe; diarrhea, watery and severe, which may also be bloody; fever
This drug may cause the urine to become rust-yellow to brown. This side effect does not require medical attention.
Nitrofurantoin may cause a temporary loss of hair in some people.
More common side effects not listed above may also occur in some diseaseds. If you notice any other problems, check with your family doctor.