The drug not used as an anti-depressant is

Options

A. luminal
B. tofranil
C. mescaline
D. sulphadiazine

Explanation

To determine which drug is not used as an antidepressant, we will analyze the four drugs mentioned: Luminol, Tofranil, Mescaline, and Sulfadiazine.

### Step-by-Step Solution:

1. **Understanding Antidepressants**:
- Antidepressants are medications that help alleviate symptoms of depression, anxiety, and related conditions. They can also be referred to as tranquilizers and work by affecting neurotransmitters in the brain.

2. **Analyzing Luminol**:
- Luminol is classified as an anticonvulsant or hypnotic drug. Anticonvulsants are primarily used to control seizures. While some anticonvulsants may have sedative effects, Luminol is not primarily used as an antidepressant.

3. **Analyzing Tofranil**:
- Tofranil is known as an antidepressant drug. It is used to treat depression and can help improve mood, sleep, and appetite. Therefore, it is indeed an antidepressant.

4. **Analyzing Mescaline**:
- Mescaline is classified as a hallucinogen. While it may have effects that can alter mood, it is not typically classified as a standard antidepressant. However, it has been noted for its potential to induce positive feelings in some contexts, but it is not a conventional antidepressant.

5. **Analyzing Sulfadiazine**:
- Sulfadiazine is an antibiotic used to treat infections. It does not have any properties that would classify it as an antidepressant. Antibiotics are used to combat bacterial infections and have no direct effect on mood or depression.

6. **Conclusion**:
- After analyzing all four drugs, it is clear that Sulfadiazine is the drug that is not used as an antidepressant.

### Final Answer:
The drug not used as an antidepressant is **Sulfadiazine**.

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