Tick the action mechanism of anticancer drugs belonging to plant alkaloids:

Correct Answer: C

Rationale: The correct answer is C: Mitotic arrest at metaphase. Plant alkaloids like vinca alkaloids and taxanes disrupt microtubule function, leading to mitotic arrest at metaphase. This prevents cell division and ultimately inhibits cancer cell growth. Option A is incorrect because plant alkaloids do not directly inhibit DNA-dependent RNA synthesis. Option B is incorrect as cross-linking of DNA is not a mechanism of action for plant alkaloids. Option D is incorrect as plant alkaloids do not target aromatases. In summary, the correct mechanism for plant alkaloids is disrupting microtubule function, leading to mitotic arrest at metaphase.

Correct Answer: A

Rationale: The correct answer is A: Hydrochlorothiazide. This diuretic is appropriate for a patient with hypertension due to its ability to reduce blood volume and lower blood pressure. It is often recommended as a first-line treatment for essential hypertension. Propranolol (B) is a beta-blocker that may not be as effective as a diuretic in this case. Captopril (C) is an ACE inhibitor that may be used as an alternative, but not as the most appropriate choice. Clonidine (D) is a centrally acting alpha-2 agonist and typically considered a second-line treatment option.

Correct Answer: B

Rationale: In this scenario, the correct answer is B) Procainamide. Procainamide is a class I antiarrhythmic agent that has been associated with drug-induced lupus erythematosus (DILE). The presentation of fatigue, low-grade fever, and joint pain in the patient suggests a possible onset of systemic lupus erythematosus (SLE) due to procainamide therapy. Lidocaine (Option A) is not associated with causing DILE. Quinidine (Option C) is also not typically linked to drug-induced lupus. Flecainide (Option D) is a class Ic antiarrhythmic agent and is not commonly known to cause DILE. Educationally, it is crucial for healthcare professionals to be aware of the potential adverse effects of medications, especially in the case of antiarrhythmic agents which can have significant systemic impacts. Understanding the side effect profiles of different drugs helps in making informed decisions regarding treatment plans and managing patient care effectively. Monitoring for signs and symptoms of adverse drug reactions is essential in ensuring patient safety and well-being.

Correct Answer: B

Rationale: Cardiac glycosides are a group of medications used to treat heart conditions by increasing the strength of the heart muscle contractions. Strophanthus gratus is the correct plant source of cardiac glycosides. It contains active compounds like ouabain and strophanthin, which are used in the production of cardiac glycoside medications like digoxin. Rauwolfia serpentina, on the other hand, is the source of reserpine, a medication used to treat high blood pressure and certain psychiatric disorders, but not cardiac glycosides. Ricinus communis is the castor oil plant, which is not a source of cardiac glycosides but is known for its oil. Atropa belladonna is a plant that contains toxic alkaloids like atropine and scopolamine, not cardiac glycosides. In an educational context, understanding the sources of medications is crucial for healthcare professionals to ensure safe and effective treatment. Knowing the correct plant sources of drugs helps in proper prescribing, dosage calculation, and potential interactions. This knowledge is essential for pharmacists, nurses, and other healthcare providers involved in patient care.

Correct Answer: B

Rationale: The correct answer is B) Cholestyramine. Cholestyramine is a bile acid sequestrant that works by binding to bile salts in the intestines, preventing their reabsorption. This action leads to increased excretion of bile salts in the feces, which in turn stimulates the liver to use cholesterol to synthesize more bile salts, thus reducing the overall cholesterol levels in the body. A) Clofibrate is a fibric acid derivative that primarily works by activating peroxisome proliferator-activated receptor alpha (PPAR-alpha) to increase lipoprotein lipase activity and decrease triglyceride levels. It does not interfere with intestinal absorption of bile salts and cholesterol. C) Lovastatin is a statin drug that inhibits HMG-CoA reductase, an enzyme involved in cholesterol synthesis in the liver. It does not interfere with intestinal absorption of bile salts and cholesterol but instead reduces cholesterol production. D) Bezafibrate is another fibric acid derivative similar to clofibrate, which also works through PPAR-alpha activation to lower triglycerides and increase HDL cholesterol levels. It does not interfere with intestinal absorption of bile salts and cholesterol. Educationally, understanding the mechanism of action of drugs used to manage cholesterol levels is crucial for healthcare professionals. Knowing how each drug interacts with the body allows for informed decision-making when selecting the most appropriate drug for a patient based on their unique needs and health conditions. This knowledge also helps in monitoring and managing potential side effects and drug interactions effectively.