Correct Answer: C

Rationale: The correct answer is C. Ceftriaxone, a cephalosporin antibiotic, has a cross-sensitivity with penicillin antibiotics like piperacillin. Therefore, a severe allergy to penicillin or penicillin-related antibiotics would be a contraindication to ceftriaxone. Choices A, B, and D are incorrect because they are not associated with a known cross-sensitivity with ceftriaxone.

Correct Answer: D

Rationale: Acetaminophen is the preferred analgesic for clients with peptic ulcer disease because it does not cause gastrointestinal irritation, unlike Ibuprofen, Naproxen, and Aspirin, which can exacerbate peptic ulcer symptoms and lead to gastrointestinal complications.

Correct Answer: A

Rationale: To calculate the dosage per dose, first, convert the toddler's weight from pounds to kilograms: 22 lb / 2.2 = 10 kg. Then, multiply the weight by the dosage: 4 mg 10 kg = 40 mg/day. Since this total daily dose is divided into 2 equal doses, the nurse should administer 20 mg per dose. Therefore, the correct answer is 20 mg. Choice B (15 mg) is incorrect because it does not account for the correct weight conversion and dosage calculation. Choice C (10 mg) is incorrect as it only considers the weight conversion but doesn't multiply it by the dosage. Choice D (30 mg) is incorrect as it miscalculates the dosage by not dividing the total daily dose into 2 equal parts.

Correct Answer: A

Rationale: The correct answer is A: Stress fractures. Long-term prednisone therapy can lead to osteoporosis, which increases the risk of stress fractures. Option B, orthostatic hypotension, is not a common adverse effect associated with prednisone use. Option C, gingival ulcerations, is more commonly associated with conditions like periodontal disease or poor oral hygiene rather than prednisone therapy. Option D, weight loss, is not a typical adverse effect of prednisone; in fact, weight gain is more common due to prednisone's impact on metabolism.

Correct Answer: D

Rationale: The correct answer is D: Reduces ammonia levels. Lactulose is used to reduce blood ammonia levels in clients with hepatic encephalopathy. Options A, B, and C are incorrect because lactulose does not have the therapeutic effect of increasing blood pressure, preventing esophageal bleeding, or decreasing heart rate.