A nurse is caring for a client who is taking warfarin and reports taking several new herbal supplements. The nurse should identify that which of the following supplements is contraindicated for concurrent use with warfarin?

A) "Call 911 if pain persists 30 minutes after taking one tablet": This instruction is not accurate and could potentially delay appropriate medical intervention for angina. Nitroglycerin sublingual tablets are rapid-acting vasodilators used to relieve acute angina symptoms. If chest pain persists after taking one tablet, the client should take another tablet after 5 minutes. If the pain persists after a total of three tablets, the client should seek emergency medical assistance.

B) "Place the tablet under the tongue until dissolved": This instruction is correct. Nitroglycerin sublingual tablets should be placed under the tongue and allowed to dissolve completely. Sublingual administration allows for rapid absorption of the medication into the bloodstream, providing quick relief of angina symptoms.

C) "Store the tablets in a refrigerator in a plastic container": This instruction is incorrect. Nitroglycerin sublingual tablets should be stored in their original container at room temperature, away from moisture and heat. Storing them in the refrigerator could alter their effectiveness.

D) "Take a tablet every 10 minutes until the pain subsides": This instruction is incorrect and potentially dangerous. Nitroglycerin sublingual tablets should be taken as directed by the healthcare provider or based on the client's angina management plan. Typically, the client should take one tablet at the onset of angina symptoms and repeat the dose every 5 minutes if the pain persists, up to a maximum of three tablets within 15 minutes. Taking a tablet every 10 minutes without regard to symptom relief or maximum dosage limits could lead to hypotension and other adverse effects.

A) Administer the insulin within 20 min of preparing it: This statement is incorrect. Insulin should be administered immediately after mixing short-acting insulin with NPH insulin, but the 20-minute time frame is not accurate. It's crucial to follow the specific instruc’ions provided by the healthcare provider or the manufacturer for timing of administration.

B) Inject air into the vial to withdraw the short-acting insulin: This is the correct action. When mixing short-acting insulin with NPH insulin from two vials, the nurse should first inject air into the NPH insulin vial, withdraw the correct dose of air into the syringe, and then inject the air into the short-acting insulin vial. This prevents the creation of a vacuum in the vial and facilitates easier withdrawal of the medication.

C) Use two separate syringes to mix the insulin: Using two separate syringes is unnecessary and may increase the risk of dosing errors or contamination. Mixing insulin from two vials can be done using a single syringe by following proper aseptic technique and the correct sequence of steps.

D) Ensure the NPH insulin is drawn into the syringe first: This statement is incorrect. When mixing short-acting insulin with NPH insulin, the short-acting insulin should be drawn into the syringe first, followed by the NPH insulin. Drawing the NPH insulin first could lead to contamination of the short-acting insulin vial with NPH insulin, potentially altering its pharmacological properties.