Nitrofurantoin 100 mg is an oral antibiotic belonging to the anti-infectives class of medicines and is used to treat urinary tract infections (UTIs) 

More Common  

1. Changes in facial skin color  
2. Chest pain  
3. Chills  
4. Cough  
5. Fever  
6. General feeling of discomfort or illness  
7. Hives, itching, skin rash  
8. Hoarseness  
9. Joint or muscle pain  
10. Sudden trouble swallowing or breathing  
11. Swelling of the face, mouth, hands, or feet  
12. Trouble breathing 

Less Common 

1. Black, tarry stools 
2. Blood in the urine or stools 
3. Burning, numbness, tingling, or painful sensations 
4. Dizziness 
5. Drowsiness 
6. Headache 
7. Pinpoint red spots on the skin 
8. Sore throat 
9. Unsteadiness or awkwardness 
10. Unusual bleeding or bruising 
11. Unusual tiredness or weakness 
12. Weakness in the arms, hands, legs, or feet 

Nitrofurantoin works by killing bacteria. It does this by blocking the bacteria from making their cell walls, which are essential for their survival. Without a strong cell wall, bacteria burst and die, helping the body fight the infection.

Allergy or Hypersensitivity

Avoid nitrofurantoin if you are allergic to nitrofurantoin. Taking it may cause serious allergic reactions like rash, swelling of the face or lips, breathing difficulty, or severe itching. Always inform your doctor about past drug allergies.

Severe kidney disease

Since nitrofurantoin is eliminated through the kidneys, people with severe kidney problems need dose adjustments to prevent drug buildup and toxicity. So, consult a doctor before using it.

Pregnancy and Breastfeeding

 Nitrofurantoin is generally considered safe in pregnancy and breastfeeding, but it should only be used if prescribed by a doctor.

Nitrofurantoin can be taken with or without food but taking it after meals can help reduce stomach irritation. Dairy products like milk, cheese, or yogurt are generally safe to consume, but alcohol should be avoided, as it may increase side effects or reduce the medicine’s effectiveness.

Avoid taking nitrofurantoin with the following medicines, as it may increase or decrease the desired effect, or in worse cases, it could be fatal:

IUPAC (International Union of Pure and Applied Chemistry)/ Chemical name

1-[(E)-(5-nitrofuran-2-yl)methylidene amino] imidazolidine-2,4-dione

Daily dose

Take Nitrofurantoin exactly as your doctor recommends. The dose may change based on your condition and how well you respond. Do not take more than prescribed without consulting your doctor.

Missed Dose

If you forget to take your medicine, take the medication as soon as you remember. If it’s nearly time for your next dose, skip the missed one and continue with your regular schedule. Always consult the doctor before making any changes to your dosage.

Overdose

 It is not recommended to take more than 600 mg of nitrofurantoin per day. Overdose may cause severe nausea, vomiting, diarrhea, dizziness, confusion, or seizures (fits). Seek immediate medical attention if any of these occur.

1. Store the medicine at room temperature. 
2. Keep away from sunlight and moisture. 
3. Keep out of reach of children. 

1. Take Nitrofurantoin exactly as prescribed by your doctor, at the same time each day. 
2. Do not stop taking nitrofurantoin without your doctor’s approval, even if you feel better. 
3. If you forget to take nitrofurantoin, take it as soon as you remember. If it’s almost time for your next dose, skip the missed dose. 

Nitrofurantoin 100 mg is an antibiotic from the urinary anti‑infective drug class, FDA‑approved mainly for treating bladder and urinary tract infections. It works by damaging bacterial DNA and stopping its growth. Common side effects of the medication include nausea, headache, dizziness, stomach upset, rash, and sometimes shortness of breath. It should be taken with food to improve absorption and reduce stomach upset. People with severe kidney disease, liver problems, or late pregnancy should avoid it. Taking more than 600 mg per day can cause overdosing effects like vomiting, dizziness, nerve damage, and lung or liver injury.

What are the uses of nitrofurantoin tablets?

Nitrofurantoin is mainly used to treat and prevent urinary tract infections, especially bladder infections, and is sometimes prescribed long‑term to stop recurrent UTIs. It is not effective for kidney infections or infections outside the urinary tract.

What is the mechanism of action of nitrofurantoin?

Nitrofurantoin works by entering bacterial cells and being reduced to reactive compounds that damage their DNA, proteins, and cell walls, which stops the bacteria from growing and eventually kills them.

What are the side effects of Nitrofurantoin 100 mg tablets?

Nitrofurantoin commonly causes mild stomach upset, nausea, vomiting, headache, dizziness, and changes in urine color, but in rare cases it can lead to serious lung, liver, or nerve problems.

What is the drug class of nitrofurantoin?

Nitrofurantoin belongs to the anti-infective class of antibiotics.

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