Pharmacology for Medical Assistants Flashcards

Which abbreviation on a prescription means 'take as needed'?

Answer: PRN

PRN (pro re nata) is the Latin abbreviation meaning 'as needed,' indicating the medication is taken only when required.

A patient is prescribed digoxin and their potassium level is low. What is the primary concern?

Answer: Hypokalemia increases the risk of digoxin toxicity

Hypokalemia potentiates digoxin toxicity because potassium and digoxin compete for the same receptor site on heart cells.

Which class of drugs works by blocking histamine H1 receptors to relieve allergy symptoms?

Answer: Antihistamines

Antihistamines competitively block H1 receptors, preventing histamine from binding and causing allergy symptoms like sneezing and itching.

What is the correct method for disposing of an unused controlled substance in a medical office?

Answer: Return it to the pharmacy or use a DEA-approved disposal method

Federal regulations require controlled substances to be disposed of through DEA-authorized collectors or reverse distributors to prevent diversion.

A physician orders 'amoxicillin 250 mg/5 mL, give 500 mg.' How many milliliters should be administered?

Answer: 10 mL

Using the ratio: 250 mg/5 mL = 500 mg/x mL; cross-multiplying gives x = 10 mL.

Which of the following is a common side effect of opioid analgesics that the medical assistant should monitor?

Answer: Constipation and respiratory depression

Opioids bind to receptors in the GI tract causing constipation and can suppress the respiratory center in the brainstem causing respiratory depression.

Which federal agency regulates the scheduling of controlled substances in the United States?

Answer: DEA (Drug Enforcement Administration)

The DEA enforces the Controlled Substances Act and maintains the scheduling system that classifies drugs by their potential for abuse.