A nurse is caring for a client who has ulcerative colitis and is receiving sulfasalazine. Which of the following findings requires immediate intervention?

A. Glucosamine. Glucosamine is a supplement used to support joint health, particularly in osteoarthritis. It does not have significant interactions with digoxin and is not known to affect cardiac function or digoxin metabolism, making it safe to use concurrently.

B. Garlic. Garlic has blood-thinning properties and may mildly lower blood pressure, but it does not directly interfere with digoxin metabolism. However, clients on anticoagulants or blood pressure medications should use garlic cautiously due to its potential to enhance their effects.

C. St. John's wort. St. John’s wort induces liver enzymes that can increase the metabolism of many medications, including digoxin. This can lead to decreased digoxin levels, reducing its effectiveness and increasing the risk of uncontrolled heart failure or atrial fibrillation. Clients taking digoxin should avoid St. John’s wort to maintain therapeutic drug levels.

D. Ginkgo biloba. Ginkgo biloba is primarily used to enhance cognitive function and circulation. While it has mild blood-thinning effects, it does not significantly impact digoxin metabolism. However, caution is advised in clients taking anticoagulants or antiplatelet medications to avoid an increased risk of bleeding.

A. Levothyroxine. Levothyroxine is used to treat hypothyroidism and does not have a significant interaction with furosemide. However, both medications require careful monitoring, as hypothyroidism can affect fluid balance, but they are not contraindicated together.

B. Cetirizine. Cetirizine is an antihistamine used to treat allergies and does not interfere with furosemide’s effects. While some antihistamines can cause mild fluid retention, this does not significantly impact furosemide therapy, making them safe to use together.

C. Lithium carbonate. Furosemide is a loop diuretic that increases sodium excretion. Since lithium is excreted through the kidneys in a sodium-dependent manner, a loss of sodium due to diuretic use can lead to reduced lithium excretion and toxic accumulation. Clients taking lithium should avoid diuretics unless absolutely necessary, and their lithium levels must be carefully monitored if diuretics are required.

D. Albuterol. Albuterol is a bronchodilator used for conditions like asthma and COPD. While both furosemide and albuterol can cause hypokalemia, this does not make them absolutely contraindicated. Instead, potassium levels should be regularly monitored, and supplementation may be needed if hypokalemia develops.