A patient asks the nurse about the uses of echinacea. Which use will the nurse include in the response?

Correct Answer: B

Rationale: The correct answer is B: Boosting the immune system. Echinacea is commonly used for its immune-boosting properties due to its ability to stimulate the immune system. It can help the body fight off infections and illnesses. Rationale: 1. Echinacea has been traditionally used for its immune-enhancing effects. 2. Research studies have shown that echinacea can increase the production of white blood cells, which are crucial for fighting infections. 3. Echinacea is often recommended to shorten the duration of colds and flu by supporting the immune response. 4. Memory enhancement (A), improving mood (C), and promoting relaxation (D) are not commonly associated with echinacea use based on scientific evidence.

Correct Answer: A

Rationale: The correct answer is A: Change in receptors, loss of them or exhaustion of mediators. Tolerance and drug resistance often occur due to changes in receptors, such as downregulation or desensitization, leading to decreased drug efficacy. Loss of receptors or exhaustion of mediators can also contribute to reduced drug response over time. Explanation of why other choices are incorrect: B: Increased receptor sensitivity would not lead to tolerance or drug resistance, as it would result in enhanced drug effects. C: Decreased metabolic degradation would increase drug levels in the body, potentially leading to increased drug effects rather than tolerance. D: Decreased renal tubular secretion may alter drug excretion but would not directly cause tolerance or drug resistance.

Correct Answer: C

Rationale: The correct answer is C: Bupivacaine. Bupivacaine is used for spinal anesthesia due to its long duration of action and potency. It provides effective anesthesia for surgeries and pain management. Procaine (A) is not commonly used for spinal anesthesia due to its short duration of action. Lidocaine (B) is used more for regional anesthesia and nerve blocks. Dupivacaine (D) is a duplicate choice and not a valid option. In summary, bupivacaine is the preferred choice for spinal anesthesia due to its duration of action and efficacy.

Correct Answer: C

Rationale: Step-by-step rationale: 1. Succinylcholine is a depolarizing agent because it acts as a nicotinic acetylcholine receptor agonist. 2. It causes initial depolarization of the motor end plate leading to muscle fasciculations. 3. By maintaining depolarization, it prevents repolarization and muscle contraction, inducing muscle relaxation. Summary: A. Vecuronium is a non-depolarizing agent that blocks acetylcholine receptors. B. Scopolamine is an anticholinergic drug used for motion sickness. D. Hexamethonium is a ganglionic blocker used for hypertension.

Correct Answer: B

Rationale: The correct answer is B: A decrease in intraocular pressure. Depolarizing blockade, such as with succinylcholine, leads to sustained depolarization of the neuromuscular junction, causing muscle paralysis. This can result in hyperkalemia due to potassium release from muscles, emesis due to stimulation of chemoreceptors, and muscle pain due to fasciculations. Intraocular pressure is not affected by depolarizing blockade. Therefore, a decrease in intraocular pressure is not an effect seen with depolarizing blockade, making choice B the correct answer.