Cyclosporin is a drug that is used as :

Options

A. Anti retro-viral drug
B. Immunosuppressant
C. Immuno-modulator
D. Immuno vaccine

Answer

**Step-by-Step Text Solution:**

1. **Understanding Cyclosporin**: Cyclosporin is a drug that is derived from a fungus. It is primarily known for its role in medical treatments.

2. **Function of Cyclosporin**: The main function of cyclosporin is to act as an immunosuppressant. This means it suppresses or decreases the immune system's activity.

3. **Why Use Immunosuppressants?**: Immunosuppressants like cyclosporin are used in situations where the immune response needs to be reduced. This is particularly important in cases of organ transplants.

4. **Organ Transplantation Context**: When a new organ is transplanted from a donor to a recipient, the recipient's immune system may recognize the new organ as foreign due to the presence of different antigens. This can trigger an immune response that may reject the transplanted organ.

5. **Role of Cyclosporin in Transplants**: To prevent the immune system from attacking the transplanted organ, cyclosporin is administered to the recipient. This helps to ensure the acceptance of the new organ and reduces the risk of rejection.

6. **Clarifying Misconceptions**: It is important to differentiate cyclosporin from other types of drugs:
- It is not an antiretroviral drug (which targets retroviruses like HIV).
- It is not an immunomodulator (which would enhance immune response).
- It is not a vaccine (which would stimulate the immune system).

7. **Conclusion**: Therefore, the correct use of cyclosporin is as an immunosuppressant, particularly in the context of organ transplantation.

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