Gastrointestinal irritation cardiovascular effects including tachycardia arrhythmias and orthostatic hypotension mental disturbances and withdrawal are possible adverse effects of:

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: C

Rationale: The correct answer is C: Haloperidol. Haloperidol is considered a typical antipsychotic drug due to its high affinity for dopamine D2 receptors and its strong dopamine-blocking effects. Typical antipsychotics primarily target dopamine receptors, leading to the alleviation of positive symptoms of psychosis. Clozapine (A), Quetiapine (B), and Olanzapine (D) are atypical antipsychotics, as they target multiple neurotransmitter systems, including serotonin and dopamine. They are preferred for their reduced risk of extrapyramidal side effects compared to typical antipsychotics.

Correct Answer: D

Rationale: Tricyclic antidepressants inhibit the reuptake of both norepinephrine and serotonin in the brain, making them mixed norepinephrine and serotonin reuptake inhibitors. This mechanism contributes to their antidepressant effects. Options A and C are incorrect as tricyclic antidepressants are not highly selective for either serotonin or norepinephrine reuptake. Option B is incorrect as tricyclic antidepressants are not monoamine oxidase inhibitors. Thus, the correct answer is D due to the dual mechanism of action of tricyclic antidepressants on norepinephrine and serotonin reuptake.

Correct Answer: B

Rationale: The correct answer is B: Piracetam. Piracetam is a CNS stimulant known for improving cognitive function and memory, making it beneficial in pediatric medicine for enhancing learning abilities and school performance. It does not have the same potential for abuse or addiction as amphetamines (choice D). Meridil (choice A) and Bemegride (choice C) are not commonly used CNS stimulants in pediatric medicine and do not have the same cognitive-enhancing effects as Piracetam.

Correct Answer: C

Rationale: The correct answer is C because psychosis with visual and auditory hallucinations is not a common characteristic of cocaine abstinent syndrome. A: Feeling of depression, irritability, confusion, insomnia in the initial days is common due to withdrawal symptoms. B: Depression, apathy, excessive appetite, and the wish to sleep in the subsequent days are typical withdrawal symptoms. D: A new attack of depression, anxiety, irritability, dullness, and intense thirst for cocaine after initial improvement is consistent with the stages of cocaine abstinent syndrome.