How to Use Antibiotics: 10 Essential Do’s and Don’ts

Antibiotics are life-saving medicines used to treat bacterial infections. However, using them incorrectly fuels Antimicrobial Resistance (AMR)—a global health threat that caused over 20,000 resistant bloodstream infections in the UK last year alone.

Follow these 10 rules to ensure your treatment is safe and effective.

5-Second Summary: The “Golden Rules”

• Only take them if prescribed: Antibiotics do not kill viruses (colds/flu).

• Follow the dose exactly: Stick to the timings and duration on the label.

• Never share: Your prescription is tailored to your weight, age, and infection.

• Finish the course: Unless your doctor specifically tells you otherwise.

• Dispose safely: Never bin or flush leftover pills. Take them to a pharmacy.

1. DON’T Use Antibiotics for Viral Infections

Antibiotics only work against bacteria. They have zero effect on viruses like the common cold, most sore throats, or the flu. Taking them for a virus won’t make you feel better and could cause side effects like diarrhoea.

2. DO Take Your Medication at Specific Intervals

To kill bacteria effectively, the level of medicine in your blood needs to stay constant.

• 3 times a day usually means every 8 hours (e.g., 7 am, 3 pm, 11 pm).

• Set an alarm to ensure you don’t miss a dose.

3. DO Complete the Prescribed Course

Even if you feel better after 48 hours, some bacteria may still be alive. Stopping early allows the strongest bacteria to survive and multiply, potentially leading to a more severe, resistant infection.

2026 Update: While some modern NHS guidelines now favor shorter 3 or 5-day courses, you must finish the specific length your doctor prescribed.

4. DON’T Crush or Break Tablets Without Asking

Many antibiotics have a “special coating” to protect your stomach or to ensure the medicine is released slowly. Breaking a tablet can destroy this coating, making the drug ineffective or causing a stomach upset.

5. DO Be Mindful of Food and Drink

What you eat can interfere with how your body absorbs the drug:

• Dairy: Calcium in milk can bind to some antibiotics (like Tetracyclines), preventing absorption.

• Grapefruit Juice: Can interfere with the enzymes that break down certain medications.

• Alcohol: While not all antibiotics react with alcohol, some (like Metronidazole) can cause severe vomiting and heart palpitations if mixed with even small amounts.

6. DON’T Share Your Prescription

What worked for your friend’s chest infection might be the wrong “class” of antibiotic for yours. Sharing also leads to under-dosing, which is a primary driver of superbugs.

7. DO Disclose Other Medications

Antibiotics can interact with:

• The Contraceptive Pill: Some antibiotics may reduce its effectiveness.

• Blood Thinners (Warfarin): Can increase the risk of bleeding.

• Antacids: Heartburn medication can stop antibiotics from being absorbed.

8. DO Return Leftover Medication to a Pharmacy

Never throw antibiotics in the household bin or flush them down the toilet. This allows traces of the drugs to enter the water system and soil, teaching environmental bacteria how to become resistant.

• All UK pharmacies are legally required to accept and safely incinerate leftover medicines for free.

9. DO Watch for Side Effects

Common side effects include nausea, bloating, or thrush (yeast infections).

• Seek immediate help if you develop a “hives” rash, swelling of the face, or difficulty breathing, as these are signs of a serious allergic reaction.

10. DON’T “Save” Antibiotics for Later

If you have leftover pills, it usually means you didn’t finish your course correctly. Never “self-diagnose” a future illness and take old pills; they may be expired or the wrong type for your new symptoms.

Why This Matters: The Threat of AMR

By 2026, antibiotic resistance has become a leading cause of death globally. By following these do’s and don’ts, you aren’t just protecting your own health—you are helping to keep these vital medicines working for future generations.