Isoniazid 300mg

Isoniazid 300mg — Uses and Benefits

Isoniazid 300mg is mainly used to treat and prevent tuberculosis (TB), a bacterial infection that commonly affects the lungs but can also affect other body parts.

WHAT THIS MEDICINE IS USED FOR

• Treatment of active pulmonary (lung) tuberculosis, usually with other anti-TB drugs
• Treatment of tuberculosis affecting other organs
• Preventive treatment for people at high risk of developing TB, such as close contacts of TB patients
• Preventive therapy in people with latent (inactive) TB infection

HOW IT WORKS

• Isoniazid enters TB bacteria and blocks a substance they need to build their outer cell wall
• Without this cell wall component, the bacteria cannot grow or multiply and eventually die
• It works best against actively dividing TB bacteria, so it is often combined with other drugs to attack bacteria in different stages

WHAT IT IS NOT USED FOR

• Ordinary bacterial infections like throat, urine or skin infections
• Viral infections such as cold, flu or COVID-19
• Fungal infections
• As a standalone painkiller or fever medicine

How to Use Isoniazid 300mg

HOW TO TAKE IT

• Take exactly as prescribed by your doctor, usually once daily
• Take on an empty stomach, at least 30 minutes before or 2 hours after food, unless your doctor advises otherwise
• Swallow the tablet with a full glass of water
• Do not stop the medicine even if you feel better; complete the full course as advised, since stopping early can lead to drug-resistant TB
• Your doctor may also prescribe vitamin B6 (pyridoxine) along with this medicine to reduce nerve-related side effects
• Avoid alcohol during treatment as it increases the risk of liver problems

IF YOU MISS A DOSE

• Take it as soon as you remember on the same day
• If it is almost time for the next dose, skip the missed dose and continue your normal schedule
• Do not take double doses to make up for a missed one
• Try to take the medicine at the same time every day to avoid missing doses

STORAGE

• Store at room temperature, away from direct sunlight and moisture
• Keep out of reach of children
• Do not use beyond the expiry date printed on the pack

Isoniazid 300mg — Side Effects

COMMON SIDE EFFECTS

• Nausea
• Loss of appetite
• Mild stomach upset
• Tiredness

LESS COMMON SIDE EFFECTS

• Tingling or numbness in hands and feet
• Headache
• Dizziness
• Dry mouth

SERIOUS SIDE EFFECTS — STOP AND SEE A DOCTOR IMMEDIATELY

• Yellowing of skin or eyes, dark urine (signs of liver problems)
• Severe stomach pain or persistent vomiting
• Unusual bleeding or bruising
• Fever with rash, joint pain or swollen glands
• Blurred vision or eye pain
• Signs of severe allergic reaction such as difficulty breathing, swelling of face or lips, severe skin rash
• Seizures or unusual behaviour changes

This is not a complete list. Report any unusual or persistent symptom to your doctor or pharmacist.

Isoniazid 300mg — Safety Information and Precautions

This medicine is available only with a valid doctor's prescription in India.

DO NOT TAKE THIS MEDICINE IF YOU

• Are allergic to isoniazid or any of its ingredients
• Have had liver damage caused by isoniazid in the past
• Have severe active liver disease, unless your doctor decides the benefit outweighs the risk

TELL YOUR DOCTOR BEFORE STARTING IF YOU

• Have any existing liver or kidney disease
• Drink alcohol regularly
• Have diabetes or nerve-related problems
• Are pregnant, planning pregnancy, or breastfeeding
• Have a history of seizures or mental health conditions
• Are malnourished or have poor diet

MEDICINES THAT CAN INTERACT

• Rifampicin and other anti-TB drugs
• Paracetamol, when used regularly in high amounts
• Anti-epileptic medicines like phenytoin and carbamazepine
• Antacids containing aluminium, which can reduce absorption
• Certain antifungal medicines
• Warfarin and other blood-thinning medicines

Always share a complete list of your current medicines and supplements with your doctor.

FREQUENTLY ASKED QUESTIONS

Can I stop the medicine once my symptoms improve?

No, you must complete the full course as prescribed even if you feel better, otherwise the TB infection can return and become drug-resistant.

Why is vitamin B6 given with this medicine?

Isoniazid can cause nerve-related side effects like tingling and numbness, and vitamin B6 helps prevent this, especially in people at higher risk.

Can I drink alcohol while taking this medicine?

• It is best to avoid alcohol completely during treatment as it increases the risk of liver damage.
• Doctor ya pharmacist se salah lein.