Which of the following statement is not correct?

Correct Answer: A

Rationale: The correct answer is A because alpha agonists cause mydriasis (pupil dilation), not miosis (pupil constriction). Alpha agonists like phenylephrine work by stimulating alpha receptors in the iris dilator muscle, leading to pupil dilation. Therefore, choice A is incorrect. Choices B, C, and D are incorrect because alpha agonists do cause mydriasis, beta antagonists do decrease the production of aqueous humor, and alpha agonists do increase the outflow of aqueous humor from the eye, respectively.

Correct Answer: B

Rationale: The correct answer is B: Triazolam. Triazolam has the shortest elimination half-life among the options provided, typically around 2-5 hours. This is due to its rapid metabolism and elimination from the body. In comparison, Temazepam (A) has a longer half-life of around 8-20 hours, Flurazepam (C) has a half-life of 40-250 hours, and Diazepam (D) has a half-life of 20-100 hours. Therefore, Triazolam is the best choice for short-term hypnotic effects due to its quick elimination from the body.

Correct Answer: A

Rationale: The correct answer is A: Carbamazepine. This drug is the drug of choice for partial seizures due to its efficacy in controlling focal seizures and its broad spectrum of activity. Carbamazepine works by blocking voltage-gated sodium channels, reducing neuronal excitability. Rationale: - Carbamazepine is a common first-line treatment for partial seizures. - It is effective in controlling focal seizures. - It has a broad spectrum of activity against various types of seizures. - Carbamazepine's mechanism of action involves blocking sodium channels, reducing neuronal excitability. Summary of other choices: - B: Ethosuximide is primarily used for absence seizures, not partial seizures. - C: Diazepam is a short-acting benzodiazepine used for acute seizure management, not as a primary treatment for partial seizures. - D: Lamotrigine is more commonly used for generalized seizures and may not be as effective for controlling partial seizures.

Correct Answer: C

Rationale: Rationale: 1. Levodopa is a dopamine precursor used in Parkinson's disease. 2. Gastrointestinal irritation is a common side effect due to increased dopamine in the gut. 3. Cardiovascular effects like tachycardia and hypotension can occur due to dopamine's influence on the heart. 4. Mental disturbances and withdrawal may result from dopamine fluctuations. 5. Amantadine (A) and Selegiline (D) do not typically cause these specific side effects. 6. Benztropine (B) is an anticholinergic used to treat extrapyramidal symptoms, not known for these adverse effects.

Correct Answer: D

Rationale: Step-by-step rationale: 1. Methadone causes tolerance and physical dependence more slowly than morphine due to its longer half-life. 2. Methadone is more effective orally as it has high bioavailability compared to morphine. 3. Withdrawal from methadone is less severe but more prolonged, making it easier to taper off. 4. Therefore, all the statements are true, making option D the correct answer. Summary: A. Incorrect - Methadone causes tolerance and physical dependence more slowly than morphine. B. Incorrect - Methadone is more effective orally compared to morphine. C. Incorrect - Withdrawal from methadone is less severe but more prolonged.