Chemistry In Everyday Life

Answer (b) Bithionol

Out of the drugs listed, **Bithionol** is not a neurologically active drug. Here's a brief explanation of each:

1. Veronal (Barbital): This is a barbiturate, a type of drug that acts as a central nervous system depressant. It is used for its sedative and hypnotic properties.

2. Bithionol: This is an anthelmintic and antiprotozoal drug. It is used to treat parasitic infections such as liver flukes and lung flukes. It does not have effects on the nervous system and is not used for neurological purposes.

3. Equanil (Meprobamate): This is an anxiolytic, a drug used to treat anxiety disorders. It has effects on the central nervous system and acts as a muscle relaxant and sedative.

4. Nardil (Phenelzine): This is a monoamine oxidase inhibitor (MAOI) used as an antidepressant. It affects the central nervous system by increasing the levels of certain neurotransmitters.

Therefore, Bithionol is the drug among the options that is not neurologically active.

Analysis of drug options:

• Salvarsan: Arsenic-containing antibacterial (not antidepressant)
• Ofloxacin: Fluoroquinolone antibiotic
• Erythromycin: Macrolide antibiotic
• Serotonin: Neurotransmitter (5-HT), target of SSRIs - selective serotonin reuptake inhibitors (antidepressant mechanism)
• Chloroxylenol: Antiseptic/disinfectant

Key point: While serotonin itself isn't administered as a drug, it's the biochemical target of most antidepressant medications.

Thus, the correct option is (D): Serotonin.