A patient is to receive a chemotherapy protocol that includes an alkylating agent, an antimetabolite, and an antitumor antibiotic. What is the nurse's best response when the patient asks the nurse why so much chemotherapy is needed?

Correct Answer: B

Rationale: Combination chemotherapy is used to target cancer cells at different stages of the cell cycle and through multiple mechanisms of action. Alkylating agents, antimetabolites, and antitumor antibiotics each work differently: alkylating agents damage DNA, antimetabolites interfere with DNA synthesis, and antitumor antibiotics inhibit RNA synthesis. By combining these drugs, the treatment can kill more cancer cells and reduce the likelihood of resistance. This approach maximizes tumor cell killing while minimizing the risk of relapse. Dose-limiting toxicities still exist, but the combination strategy allows for lower doses of each drug, reducing individual side effects.

Correct Answer: C

Rationale: ACE inhibitors work by inhibiting the enzyme angiotensin-converting enzyme (ACE) in the renin-angiotensin-aldosterone system (RAAS). By inhibiting ACE, the conversion of angiotensin I to angiotensin II is blocked. Angiotensin II is a potent vasoconstrictor and also stimulates the release of aldosterone from the adrenal glands. Aldosterone is a hormone that acts on the kidneys to increase reabsorption of sodium and water, leading to increased blood volume and pressure. By inhibiting aldosterone secretion, ACE inhibitors reduce blood volume and lower blood pressure, making them effective in treating hypertension and heart failure.

Correct Answer: D

Rationale: Kallidin is a peptide, specifically a kinin, and is not classified as an eicosanoid. Eicosanoids are a group of lipid mediators derived from arachidonic acid or other fatty acids, including prostaglandins, prostacyclin, thromboxane, and leukotrienes. Although kallidin also plays a role in inflammation and vasodilation like some eicosanoids, it is not part of the eicosanoid family.

Correct Answer: C

Rationale: Propranolol is the drug that undergoes extensive first-pass hepatic metabolism. First-pass metabolism refers to the metabolism of a drug by the liver before it enters the systemic circulation. In the case of propranolol, a significant portion of the drug is metabolized by the liver before reaching the systemic circulation, leading to reduced bioavailability. This is why propranolol is often given in higher doses to achieve the desired therapeutic effect. Heparin, insulin, nitroglycerine, and warfarin do not undergo significant first-pass metabolism by the liver.

Correct Answer: A

Rationale: Common side effects of iron supplements include constipation, upset stomach, and nausea. Iron supplements can cause gastrointestinal side effects such as constipation, upset stomach, and nausea. These side effects usually improve over time or can be managed by taking the supplement with food or adjusting the dosage. It is important to speak with a healthcare provider if these side effects persist or worsen.