# A pharmaceutical company is developing a new painkiller from a plant extract. Before the medicine can be sold to the public, it must pass through a series of stages. Describe the stages that the new medicine must go through before it can be approved for use by patients.

> OCR A-Level Chemistry B: Salters (H433) — WM What's in a medicine? · Describe · 5 marks

> Many modern medicines are developed from natural sources. The active ingredient must be extracted, tested for safety and effectiveness, and approved by a regulatory authority before it can reach patients.

## Mark scheme (5 marks)

1. The active ingredient is tested in the laboratory / tested on cells or tissues (preclinical testing)
2. The medicine is tested on animals to check for safety / toxicity / side effects
3. Clinical trials are carried out on human volunteers / patients
4. A placebo is used so that the effect of the medicine can be compared to no treatment / to identify the true effect of the drug
5. The results are reviewed / approved by a regulatory authority before the medicine can be sold / used by patients

## Related

- [Revision notes for OCR A-Level Chemistry B: Salters (H433)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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Source: [GradeNine](https://www.gradenine.co.uk/q/a-pharmaceutical-company-is-developing-a-98aa7418) · Published by Druglandscape Ltd.