What is the classification of Ondansetron?

Correct Answer: C

Rationale: Ondansetron is classified as an antiemetic. It is commonly used to prevent nausea and vomiting caused by chemotherapy, radiation therapy, and surgery. Antiemetics work by blocking serotonin, a natural substance in the body that can trigger nausea and vomiting. Ondansetron specifically targets serotonin receptors in the brain, preventing the sensation of nausea and reducing the urge to vomit. Therefore, the correct classification for Ondansetron is as an antiemetic agent.

Correct Answer: D

Rationale: In the case of a Heparin overdose, the antidote of choice is Protamine sulfate. Heparin is a commonly used anticoagulant medication, and if an overdose occurs leading to excessive bleeding, Protamine sulfate can be administered to reverse the effects of Heparin by neutralizing its anticoagulant activity. It forms a complex with Heparin, rendering it inactive and helping to slow down or stop the bleeding. Naloxone is used as an antidote for opioid overdose, Ibutilide is used for arrhythmias, and Methylphenidate is a central nervous system stimulant commonly used to treat ADHD. But these antidotes are not appropriate for reversing the effects of a Heparin overdose.

Correct Answer: B

Rationale: Metformin is a first-line medication for the treatment of type 2 diabetes. Its primary pharmacological action is to decrease hepatic glucose production by inhibiting gluconeogenesis and glycogenolysis in the liver. This helps to lower blood glucose levels. Metformin also increases insulin sensitivity in peripheral tissues like muscle and fat, allowing tissues to better respond to insulin and take up glucose from the blood. This dual mechanism of action makes metformin an effective medication for managing blood glucose levels in patients with type 2 diabetes.

Correct Answer: A

Rationale: Warfarin is an anticoagulant medication that works by inhibiting the action of vitamin K, reducing blood clotting. In cases of Warfarin overdose or excessive anticoagulation resulting in bleeding complications, the antidote is vitamin K. Vitamin K helps the liver produce clotting factors, which can counteract the effects of Warfarin and restore normal blood clotting. Other options such as Naloxone, Digibind, and Flumazenil are antidotes used for specific situations like opioid overdose, digoxin toxicity, and benzodiazepine overdose, respectively, and are not relevant for Warfarin antidote.

Correct Answer: B

Rationale: The main difference between ester group local anesthetics and amide group local anesthetics lies in the way they are metabolized in the body. Esters are metabolized in the plasma by the enzyme pseudocholinesterase, while amides are metabolized in the liver. Pseudocholinesterase hydrolyzes esters into inactive metabolites, which are then excreted mainly by the kidneys. On the other hand, amides undergo hepatic metabolism by the cytochrome P450 enzyme system before being excreted by the kidneys. This key metabolic difference between esters and amides impacts their pharmacokinetics, including onset of action, duration of effect, and potential for allergic reactions.