Which medication is primarily used to treat hyperlipidemia?

Correct Answer: A

Rationale: Rationale: 1. Simvastatin is a statin drug known to lower cholesterol levels by inhibiting cholesterol synthesis. 2. Hyperlipidemia is characterized by high levels of lipids in the blood, making statins the ideal treatment. 3. Hydrochlorothiazide is a diuretic, not indicated for hyperlipidemia. 4. Albuterol is a bronchodilator used for asthma, not hyperlipidemia. 5. Diltiazem is a calcium channel blocker for hypertension, not hyperlipidemia.

Correct Answer: B

Rationale: The correct answer is B: Relaxing bronchial smooth muscle by stimulating beta-2 adrenergic receptors. Salmeterol is a long-acting beta-2 agonist that works by binding to beta-2 adrenergic receptors in the lungs, leading to the relaxation of bronchial smooth muscle. This results in bronchodilation, which helps in relieving asthma symptoms. Choice A is incorrect as salmeterol does not block the action of histamine. Choice C is incorrect as salmeterol does not inhibit the release of leukotrienes. Choice D is incorrect as salmeterol does not block acetylcholine receptors in the lungs. In summary, the correct answer B is based on the mechanism of action of salmeterol as a beta-2 adrenergic receptor agonist, leading to bronchodilation and improved breathing in asthma patients.

Correct Answer: A

Rationale: Rationale: Diphenhydramine is a first-generation antihistamine that works by blocking histamine receptors in the respiratory tract. Histamine is released during an allergic reaction and causes symptoms like a runny nose. By blocking histamine receptors, diphenhydramine effectively reduces these symptoms. Therefore, option A is correct. Option B is incorrect because diphenhydramine does not stimulate beta-2 receptors. Option C is incorrect as diphenhydramine does not increase mucus production. Option D is incorrect as diphenhydramine does not block acetylcholine receptors in the brain.

Correct Answer: B

Rationale: The correct answer is B: Dilating the bronchioles. Albuterol is a beta-2 adrenergic agonist that acts on bronchial smooth muscle to cause bronchodilation, improving airflow in patients with COPD. This effect helps relieve symptoms of bronchoconstriction and shortness of breath. Choices A, C, and D are incorrect because albuterol does not increase mucus production, decrease bronchial inflammation, or inhibit histamine release. It primarily targets bronchial smooth muscle to promote bronchodilation.

Correct Answer: B

Rationale: The therapeutic index value of 2 indicates that the toxic dose is 2 times the effective dose. To have a 50% chance of developing toxic side effects, the patient would need to take a dose that is half of the toxic dose. This means the patient would need to take 1/2 of the toxic dose at each administration. Since the therapeutic index is 2, the patient would need to divide the toxic dose into 2 equal parts, which results in 2 doses. Therefore, the correct answer is B: Two doses. Summary: A: Incorrect - Taking one dose would exceed the therapeutic index and increase the risk of toxic side effects. C: Incorrect - Not providing a clear answer. D: Incorrect - Incomplete option.