A patient taking isoniazid is worried about the negative effects of the drug. The nurse provides information knowing that which is an adverse effect of the drug?

Correct Answer: B

Rationale: Isoniazid is associated with hepatotoxicity, which can range from asymptomatic elevation of liver enzymes to severe hepatitis. Patients should be monitored for symptoms such as fatigue, nausea, and jaundice. Ototoxicity and nephrotoxicity are not common adverse effects of isoniazid. Optic neuritis is a rare side effect of ethambutol, another antitubercular drug, not isoniazid.

Correct Answer: B

Rationale: Omeprazole, a proton pump inhibitor (PPI), is most effective when taken 30 minutes before meals. This allows the medication to inhibit proton pumps during meal-stimulated acid production. Taking it after (A) or with meals (C) reduces its effectiveness. While it can be taken without regard to meals (D), taking it before meals is optimal.

Correct Answer: C

Rationale: Hair loss is a known but temporary side effect of azathioprine, an immunosuppressant used to treat autoimmune conditions. It occurs due to the drug's impact on rapidly dividing cells, including hair follicles. While distressing, this side effect is usually reversible once the medication is discontinued or the body adjusts to it. Hair loss is not typically a sign of toxicity, and reassuring the client about its temporary nature can help alleviate anxiety.

Correct Answer: D

Rationale: Emesis risk depends on chemotherapeutic emetogenicity. Cisplatin, dacarbazine, doxorubicin, and mustine are highly emetogenic, triggering vomiting via chemoreceptor zones. Vincristine, a vinca alkaloid, is least emetogenic, causing neuropathy instead, making it the exception. This lower risk reduces antiemetic needs, easing patient burden during treatment.

Correct Answer: B

Rationale: Cyanocobalamin, or vitamin B12, is essential for red blood cell production and neurological function, and its deficiency directly leads to pernicious anemia, a condition characterized by large, immature red blood cells due to impaired DNA synthesis. This occurs because B12 is crucial for folate metabolism and erythropoiesis, and without it, anemia develops, often accompanied by neurological symptoms like numbness or tingling. Pellagra, however, results from niacin (vitamin B3) deficiency, manifesting as dermatitis, diarrhea, and dementia-unrelated to B12's role. Rickets stems from vitamin D deficiency, causing bone deformities due to poor calcium absorption, not a B12 issue. Scurvy arises from vitamin C deficiency, leading to collagen breakdown and symptoms like bleeding gums, distinct from B12's hematological effects. Pernicious anemia stands out as the correct outcome because B12 deficiency disrupts bone marrow function, and it often requires pharmacotherapy, such as B12 injections, especially if absorption is impaired (e.g., due to lack of intrinsic factor). This specificity eliminates other conditions, highlighting B12's unique role in blood and nerve health.