A patient comes to the office with a chief complaint of hair loss and peeling skin. The nurse notes many vitamins and minerals are on the medication list. The patient reports using vitamins to treat liver disease. The patient's complaint may be caused by an excess of which vitamin or mineral?

Correct Answer: A

Rationale: Excessive vitamin A can cause hypervitaminosis A, leading to symptoms such as hair loss, peeling skin, and liver toxicity. Zinc (B), vitamin C (C), and vitamin D (D) are not typically associated with these symptoms. The nurse should assess the patient's vitamin A intake and advise moderation.

Correct Answer: D

Rationale: Terfenadine is a second-generation antihistamine, but it is not an H1 receptor antagonist like the other options listed. Terfenadine was once used for the treatment of allergic conditions, but it is known for its potential to cause cardiac side effects due to its interaction with other medications and prolongation of the QT interval. Consequently, terfenadine has been largely replaced by newer, safer antihistamines. The rest of the options listed (chlorpheniramine, promethazine, cimetidine, and diphenhydramine) are all H1 receptor antagonists commonly used to block the action of histamine and relieve symptoms of allergies.

Correct Answer: D

Rationale: Oxymetazoline relieves congestion quickly but risks rebound if overused. 'Take this medication exactly as directed as there is no antidote if you overdose' emphasizes adherence to prevent misuse . Hand washing and not swallowing reduce risks. It acts fast, not over days . Choice D ensures safe use, critical for nasal decongestants.

Correct Answer: A

Rationale: Indometacin, when administered rectally, bypasses first-pass metabolism, allowing rapid systemic absorption and therapeutic effect.

Correct Answer: C

Rationale: Phenobarbital, a barbiturate, binds to a distinct site on the GABA_A receptor, enhancing GABA's inhibitory effects by prolonging chloride channel opening. At high doses, it uniquely can directly open these channels without GABA, leading to profound CNS depression—useful in anesthesia or seizure control but risky due to overdose potential. Diazepam, a benzodiazepine, also acts on GABA_A receptors but only enhances GABA's effect, not independently opening channels, limiting its action to GABA availability. Ethanol affects GABA_A receptors indirectly and lacks this specific high-dose capability. Baclofen targets GABA_B receptors, influencing potassium channels, not chloride, and is unrelated to this mechanism. Dronabinol, a cannabinoid, has no GABA_A activity. Phenobarbital's ability to independently activate chloride channels at high doses distinguishes it, aligning with the scenario described and explaining its utility and risks in clinical settings.