A 30 year old manic patient was prescribed Haloperidol one week back. For the last two days he has become restless and kept pacing in the room for a day. On examinarion he was found to have tremors of hand. He is most likely suffering from

**Core Concept**
Haloperidol is a typical antipsychotic medication that can cause extrapyramidal side effects (EPS) due to its blockade of dopamine D2 receptors in the nigrostriatal pathway. This blockade disrupts the normal balance between dopamine and acetylcholine, leading to symptoms such as tremors, rigidity, and bradykinesia.

**Why the Correct Answer is Right**
The patient's symptoms of restlessness, pacing, and tremors are indicative of akathisia, a type of EPS that is characterized by subjective feelings of restlessness and objective signs of agitation. Akathisia is thought to result from the blockade of dopamine D2 receptors in the striatum, which disrupts the normal regulation of motor activity. The nigrostriatal pathway, which is involved in motor control, is also affected, leading to the development of tremors.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not provided, so we cannot evaluate it.
**Option B:** This option is not provided, so we cannot evaluate it.
**Option C:** This option is not provided, so we cannot evaluate it.
**Option D:** This option is not provided, so we cannot evaluate it.

**Clinical Pearl / High-Yield Fact**
Akathisia is often treated with beta-blockers such as propranolol, which can help to alleviate symptoms by blocking the peripheral effects of dopamine and reducing the blockade of dopamine D2 receptors in the striatum.

**Correct Answer:** A. Akathisia.

✓ Correct Answer: D. Akathesia