# Describe why antibiotics cannot be used to treat viral infections, and explain why patients prescribed antibiotics should always complete the full course of treatment.

> Cambridge International IGCSE Biology (0610) — 15.1 Drugs · Describe and Explain · 4 marks

## Mark scheme (4 marks)

1. Antibiotics cannot kill viruses because viruses do not have a cell wall (that antibiotics can destroy)
2. Viruses do not grow and reproduce in the same way as bacteria, so antibiotics cannot inhibit them
3. Completing the full course ensures all bacteria are killed
4. If the course is not completed, surviving bacteria may be antibiotic-resistant and reproduce, spreading resistance

## Key terms

- [antibiotic](https://www.gradenine.co.uk/glossary/antibiotic)

## Related

- [Revision notes for Cambridge International IGCSE Biology (0610)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe and Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/describe-why-antibiotics-cannot-be-used-183ceec5) · Published by Druglandscape Ltd.