Which statement from a client indicates understanding of the use of famotidine for peptic ulcer disease?

The statement about smoking making famotidine less effective reflects an understanding of the medication's interaction with certain lifestyle factors. Famotidine is a histamine-2 receptor antagonist that reduces stomach acid production, which is beneficial for managing conditions like peptic ulcer disease. However, smoking can increase gastric acid secretion and irritate the gastric mucosa, potentially diminishing the effectiveness of medications like famotidine. Acknowledging that smoking can impact the treatment shows the client is aware of factors that could hinder their recovery from peptic ulcers.

The other statements do not display an accurate understanding of famotidine's use. Stopping the medication prematurely could lead to a recurrence of symptoms, and taking it only when experiencing pain does not align with the treatment strategy for ulcer management. The belief that famotidine will turn stools black is incorrect; this side effect is more commonly associated with bismuth subsalicylate and certain iron supplements rather than famotidine. Thus, recognizing the impact of smoking on medication efficacy illustrates a solid comprehension of all treatment elements for peptic ulcer disease.