Ethambutol

Ethambutol

Ethambutol serves as a significant part of standard treatment protocols worldwide as one of the first-line treatments for tuberculosis (TB) over the last several years. Doctors use ethambutol to treat tuberculosis along with other medications such as isoniazid, rifampicin, and pyrazinamide. Patients taking ethambutol should monitor their health throughout the treatment. Higher dosage levels typically increase the risk of vision-related complications.

This article explains what ethambutol is, its properties, uses, proper dosing guidelines and precautions.

What is Ethambutol?

Ethambutol is an antituberculosis drug. The medication stops bacteria from growing in your body and helps your immune system fight the infection. It prevents cell wall formation in bacteria by disrupting arabinogalactan synthesis and blocks the enzyme arabinosyl transferase.

Ethambutol Tablet Uses

Doctors use this medicine to treat tuberculosis (TB), and it works with other TB medicines. Doctors also prescribe ethambutol to treat:

• Mycobacterium avium complex (MAC) infections
• Mycobacterium kansasii infections

How and When to Use Ethambutol Tablet

• You should take ethambutol once daily with or without food. Taking it with meals helps if it upsets your stomach. 
• The tablets need to be swallowed whole with water, so don't chew or crush them. 
• Take your medicine at the same time each day. If you forget about taking it on time you can set a daily alarm to remind you.
• Do not stop the medicine early as it can increase the risk of treatment failure.

Ethambutol Side Effects 

Common side effects include:

• Vision problems (notably colour blindness or visual changes)
• Joint pain and gout
• Nausea 
• Loss of appetite
• Headaches and dizziness
• Numbness in hands and feet

Precautions

• Your doctor needs to check your eyesight before treatment begins. You should contact your doctor right away if you notice any changes in your vision.
• Let your doctor know if you have kidney disease, liver problems, or gout. 
• Children under 13 years should not take ethambutol. 
• You should limit alcohol while taking this medication because it raises your risk of liver problems. 
• The medication is generally safe during pregnancy, but tell your doctor if you are pregnant or breastfeeding.
• Tell your doctor about all your medications since ethambutol reacts with many drugs.

How Ethambutol Tablet Works

Ethambutol targets specific enzymes called arabinosyltransferases (embA, embB, and embC) after entering Mycobacterium cells. These enzymes play a key role in building bacterial cell walls. The drug blocks them and prevents the formation of arabinogalactan and lipoarabinomannan - components of cell walls.

The bacterial structure weakens in two ways. These are:

• Arabinogalactan reduction creates fewer binding sites for mycolic acid
• Lipoarabinomannan decrease affects bacteria's interaction with your cells.

Ethambutol doesn't kill bacteria directly. The drug stops their multiplication and allows your immune system to clear the infection effectively.

Can I Take Ethambutol with Other Medicines?

Several medications interact with ethambutol. These are:

• Aluminum-containing antacids - a 4-hour gap after ethambutol is needed
• Anti-gout medications like allopurinol, probenecid, or febuxostat
• BCG vaccine 
• Immunosuppressant medication like azathioprine
• Levoketoconazole

Dosage Information

Your weight and TB treatment history determine the tuberculosis treatment dosage:

• First-time treatment: 15 mg/kg body weight daily 
• Previous treatment cases: 25 mg/kg daily at first, dropping to 15 mg/kg after 60 days
• Weight-based daily dosing:
  • 40-55 kg: 800 mg
  • 56-75 kg: 1200 mg
  • 76-90 kg: 1600 mg

Conclusion

Ethambutol has been the cornerstone of tuberculosis treatment worldwide. This medicine works best when combined with other TB medications, never alone. Using multiple drugs helps fight the infection and reduces the chances that bacteria will become resistant. Anyone taking ethambutol needs to watch for changes in vision and tell their doctor immediately. 

With proper medical oversight and awareness of side effects, this medication proves invaluable in fighting tuberculosis. Your doctor will support you through your treatment experience to ensure you get the perfect balance of effectiveness and safety.

FAQs

1. Is ethambutol high risk?

Ethambutol poses a moderate risk compared to other TB medications. The biggest problem involves vision problems that affect only some patients. Your risk goes up with higher doses. The good news is that most side effects go away after stopping treatment.

2. Is ethambutol a strong antibiotic?

No, ethambutol is bacteriostatic rather than bactericidal. It prevents bacteria from multiplying instead of killing them directly. This is why doctors always combine it with other TB medicines.

3. How long does ethambutol take to work?

You should start seeing improvement after several weeks of treatment. But you must take ethambutol for 6-24 months based on your condition. Your recovery depends on completing the whole treatment course.

4. What happens if I miss a dose?

Take the missed dose once you remember it. However, if it is almost time for your next dose skip the missed one and continue with your regular schedule. You should never take a double dose to catch up.

5. What happens if I overdose?

Overdose symptoms can include nausea, abdominal pain, mental confusion, hallucinations, and optic neuropathy. You need to contact emergency services immediately if an overdose happens.

6. What not to take with ethambutol?

Stay away from aluminium-containing antacids within 4 hours of taking ethambutol. Medications like disulfiram can increase neurological side effects. 

7. Who cannot take ethambutol?

Ethambutol isn't safe for people with:

• Hypersensitivity to the medication
• Known optic neuritis
• People who can't report vision changes (young children under 13, unconscious patients)

8. When should I take ethambutol?

Take ethambutol once daily at the same time each day. You can take it with or without food, but having it with meals helps reduce stomach discomfort.

9. How many days to take ethambutol?

Your treatment duration depends on your specific condition. Ethambutol is usually part of the TB treatment's intensive phase that lasts around 2 months. The complete TB treatment usually takes 6-9 months.

10. When to stop ethambutol?

Your doctor will likely stop ethambutol after lab tests show TB bacteria respond well to isoniazid and rifampin. Never stop taking this medication without your doctor's approval. You must complete the prescribed course to prevent antibiotic resistance.

11. Is it safe to take ethambutol daily?

Doctors usually prescribe ethambutol as a once daily medication. This schedule maintains steady medicine levels in your blood throughout the day. Taking the medicine as prescribed will give you the best results against TB bacteria.

12. What is the best time to take ethambutol?

A consistent daily schedule works best. You can choose morning or evening (timing doesn't matter much). You can take it with food if you experience stomach discomfort. Just remember to swallow the tablets whole with water for proper absorption.

13. What to avoid when taking ethambutol?

Avoid:

• Aluminium antacids 
• Heavy alcohol use
• Missed doses that could lead to treatment failure