Metronidazole 400 mg is an antibiotic medicine belonging to the category of nitroimidazoles. It is useful for the following indications: 

1. Stomach or intestinal infections caused by bacteria or parasites 
2. Infections of the reproductive organs, such as bacterial vaginosis 
3. Skin infections caused by bacteria 
4. Mouth or gum infections 
5. Bone or joint infections caused by bacteria 
6. Certain types of diarrhea caused by bacteria or parasites 

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

More Common  

1. Nausea or upset stomach 
2. Vomiting 
3. Diarrhea 
4. Stomach pain or cramps 
5. Metallic taste in the mouth 
6. Headache 

Less Common

1. Dizziness or feeling lightheaded 
2. Rash or itching 
3. Swelling or redness of the skin 
4. Dark urine 
5. Seizures or severe allergic reactions 

Metronidazole is an antibiotic that fights infections caused by bacteria and certain parasites. It works by entering the harmful microbes and stopping them from making the proteins and DNA they need to survive and multiply. This helps your body clear the infection, reduce symptoms like stomach pain, diarrhea, or swelling, and prevents the infection from spreading. By targeting only the harmful bacteria or parasites, it helps you get better without affecting most of the good bacteria in your body. 

Allergy or hypersensitivity

If you have ever had an allergy to metronidazole, inform your doctor before using it, as it may cause serious reactions like rash, swelling, or breathing problems. 

Pregnancy

Metronidazole may affect the developing fetus, particularly in early pregnancy. Consult with your healthcare provider before use. 

Breastfeeding

The medicine can pass into breast milk and may affect the baby’s health. Doctors usually recommend avoiding it or using an alternative while breastfeeding.

Blood Disorders (like low white blood cells)

This medicine may worsen existing blood problems or reduce your body’s ability to fight infections. 

Liver Disease

Metronidazole is processed in the liver. If your liver is not working well, the medicine can build up in your body, increasing the risk of side effects like nausea, vomiting, or confusion. 

Avoid taking caffeine containing food as they may affect medicine absorption in the body. Drinking alcohol and smoking while taking Metronidazole, or for at least 48 hours after finishing it, can cause severe reactions like nausea, vomiting, flushing, headache, or fast heartbeat. 

Avoid taking Metronidazole 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

2-(2-methyl-5-nitroimidazol-1-yl)ethanol 

Daily dose

Take Metronidazole 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

Do not take more than 750 mg of metronidazole a day, as the maximum dose increases the risk of serious side effects such as nausea, vomiting, stomach pain, dizziness, confusion, numbness, or seizures. In such a case, seek medical help immediately. 

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

Metronidazole 400 mg is an antibiotic medicine belonging to the nitroimidazole class. It is used to fight infections caused by bacteria and certain parasites, including stomach or intestinal infections, reproductive organ infections like bacterial vaginosis, skin infections, mouth or gum infections, bone or joint infections, and some types of diarrhea. It works by entering the harmful microbes and stopping them from making the proteins and DNA they need to survive, which helps your body get rid of the infection and feel better. Common side effects include nausea, vomiting, stomach pain, diarrhea, headache, and a metallic taste in the mouth. Less common side effects can include dizziness, rash, swelling, dark urine, or, in rare cases, seizures and severe allergic reactions.  

Metronidazole should be taken exactly as prescribed, usually after food, and alcohol should be avoided during treatment and for at least 48 hours after finishing it. Pregnant or breastfeeding women, people with liver problems, or those allergic to the medicine should use it only under a doctor’s advice. If severe reactions like swelling, rash, or trouble breathing occur, seek medical attention immediately. 

What are the uses of metronidazole? 

Metronidazole is used to fight infections caused by bacteria and certain parasites. It helps with stomach or intestinal infections, reproductive organ infections like bacterial vaginosis, skin infections, mouth or gum infections, bone or joint infections, and some types of diarrhea caused by bacteria or parasites. 

What are the side effects of metronidazole? 

Common side effects include nausea, vomiting, stomach pain, diarrhea, metallic taste in the mouth, and headache. Less common side effects can be dizziness, rash, swelling, dark urine, or, in rare cases, seizures and severe allergic reactions. If severe reactions like difficulty breathing, swelling, or rash occur, seek medical help immediately. 

How does metronidazole work? 

Metronidazole enters the harmful bacteria or parasites in your body and stops them from making the materials they need to survive. This helps get rid of the infection and eases symptoms like stomach upset, diarrhea, or swelling. 

What class of medicine is metronidazole? 

Metronidazole belongs to the antibiotic class called nitroimidazoles. It is used to fight infections caused by certain bacteria and parasites. 

Can I take metronidazole during pregnancy? 

Metronidazole is usually not recommended in the first trimester unless your doctor says it is necessary. It may affect the baby’s development, so always consult your doctor before taking it while pregnant. 

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