Which of the following is classified as a class IA Sodium Channel blocker?

Correct Answer: A

Rationale: The correct answer is A: Quinidine. Quinidine is a class IA antiarrhythmic drug that blocks sodium channels in a use-dependent manner, which means it preferentially blocks channels that are open or have a rapid firing rate during depolarization. This action results in a decrease in conduction velocity and refractory period. Disopyramide is a class IA antiarrhythmic but does not specifically block sodium channels. Amiodarone is a class III antiarrhythmic that primarily affects potassium channels. Propafenone is a class IC antiarrhythmic that has minimal effects on sodium channel blockade. Therefore, Quinidine is the correct choice as a class IA sodium channel blocker.

Correct Answer: A

Rationale: The correct answer is A: Elevated lipid levels. Isoflurane does not cause elevated lipid levels. Isoflurane is a general anesthetic that primarily affects the central nervous system, leading to effects like decreased respiratory function and increased blood flow to the brain. Nausea can also be a side effect of isoflurane due to its impact on the gastrointestinal system. However, there is no direct link between isoflurane and elevated lipid levels. Thus, choice A is the correct answer.

Correct Answer: D

Rationale: The correct answer is D: Sexual dysfunction. Nifedipine is a calcium channel blocker that primarily causes vasodilation by relaxing blood vessels. Sexual dysfunction is not a common side effect associated with Nifedipine use. Nausea, flushed appearance, and vertigo are potential side effects of Nifedipine due to its mechanism of action on the cardiovascular system. Therefore, D is the correct choice as it does not align with the expected side effects of Nifedipine.

Correct Answer: D

Rationale: The correct answer is D: Muscle wasting. Ibuprofen is primarily associated with gastrointestinal side effects like nausea, renal dysfunction, and anemia due to its effects on the stomach, kidneys, and blood. Muscle wasting is not a known direct effect of Ibuprofen toxicity. Ibuprofen is not typically linked to muscle-related issues, making choice D the correct answer.

Correct Answer: C

Rationale: Hydrochlorothiazide is a diuretic commonly used to treat hypertension (HTN) and congestive heart failure (CHF) by reducing blood volume and lowering blood pressure. Nephritis is an inflammatory condition of the kidneys, not typically treated with Hydrochlorothiazide as it may worsen kidney function. Hypercalciuria, excessive calcium in the urine, can be managed with Hydrochlorothiazide as it helps reduce calcium excretion. Therefore, the correct answer is C (Nephritis), as it is not typically treated with Hydrochlorothiazide due to its potential impact on kidney function.

Correct Answer: B

Rationale: The correct answer is B: Hypotension. Prednisone toxicity typically causes hypertension, not hypotension. Prednisone can lead to increased blood pressure due to its sodium-retaining effects. Cataracts (A), Psychosis (C), and Acne (D) are all known side effects of Prednisone toxicity. Cataracts can form due to long-term steroid use, psychosis can occur especially at higher doses, and acne is a common skin side effect. Therefore, hypotension is the odd one out among the choices given.

Correct Answer: B

Rationale: The correct answer is B: Liver. Warfarin is primarily metabolized in the liver by the cytochrome P450 enzyme system. The liver is responsible for breaking down and activating many drugs, including Warfarin. It is where the drug's metabolism and effects are most significant. The other choices are incorrect because Warfarin's main site of activity is in the liver, not the kidney, blood, or heart. The kidney mainly excretes the drug, while the blood carries it throughout the body, and the heart is not directly involved in Warfarin's metabolism.

Correct Answer: D

Rationale: The correct answer is D: H antagonist. Drugs ending in the suffix (tidine) typically belong to the class of histamine H2-receptor antagonists. These drugs work by blocking the action of histamine on H2 receptors in the stomach, reducing the production of stomach acid. This is commonly used to treat conditions such as peptic ulcers and gastroesophageal reflux disease. Explanation of other choices: A: Antidepressant - Drugs ending in (pramine) or (ine) are more commonly associated with antidepressants. B: Protease inhibitor - Drugs ending in (navir) are typically protease inhibitors used in antiviral therapy. C: Beta antagonist - Drugs ending in (olol) are beta-blockers, which are used to treat conditions such as hypertension and heart disease, not related to (tidine) suffix.

Correct Answer: D

Rationale: The correct answer is D: Rheumatic fever. Methotrexate is not typically used to treat rheumatic fever as it is an autoimmune inflammatory condition, not typically responsive to Methotrexate. Methotrexate is commonly used to treat sarcomas, leukemias, and ectopic pregnancies due to its ability to inhibit cell proliferation. Sarcomas and leukemias are types of cancers, while ectopic pregnancy is a condition where a fertilized egg implants outside the uterus.