A nurse is assessing a client who requests an oral contraceptive. Which of the following findings in the client's medical history should the nurse identify as a contraindication for the use of a combination oral contraceptive?

Rationale for correct choices

• Dry mouth (HEENT): Amitriptyline blocks muscarinic (acetylcholine) receptors, leading to decreased salivary gland secretion. This results in xerostomia (dry mouth), which can increase risk for dental caries, oral infections, and difficulty swallowing. Patients should be taught to increase fluid intake, chew sugarless gum, or use saliva substitutes.
• Tachycardia (Cardiovascular): TCAs inhibit norepinephrine reuptake and also have anticholinergic effects, both of which can increase heart rate. Additionally, TCAs can affect cardiac conduction (prolonged PR, QRS, QT intervals), making tachycardia and dysrhythmias important adverse effects to monitor, especially in older adults or those with cardiac disease.
• Urinary retention (Genitourinary): Anticholinergic effects reduce detrusor muscle contraction in the bladder, making it difficult to initiate urination and fully empty the bladder. This can lead to bladder distention and discomfort, particularly in older adults or those with prostate enlargement.
• Constipation (Gastrointestinal): TCAs decrease gastrointestinal motility due to their anticholinergic properties. This slows peristalsis, leading to constipation. Patients should be encouraged to increase fiber intake, fluid intake, and physical activity to prevent complications like fecal impaction.

Rationale for incorrect choices:

• Double vision: Although TCAs can cause blurred vision due to anticholinergic effects, dry mouth is a more common and expected finding emphasized in teaching.
• Sore throat: Not associated with TCA use; may indicate infection rather than medication effect.
• Chest pain: Not a typical expected side effect; could indicate a serious cardiac issue and requires immediate evaluation.
• Hypertension: TCAs are more likely to cause orthostatic hypotension due to alpha-1 blockade, not hypertension.
• Hematuria: No mechanism linking TCAs to blood in urine.
• Urinary incontinence: Opposite of expected effect; TCAs cause retention, not leakage.
• Weight loss: TCAs often cause weight gain due to increased appetite and metabolic effects.
• Diarrhea: Due to decreased GI motility, constipation—not diarrhea—is expected.

Rationale:

A. In chronic kidney disease (CKD), hemoglobin levels are typically decreased, not increased. The kidneys normally produce erythropoietin, a hormone that stimulates the bone marrow to produce red blood cells. When kidney function declines, erythropoietin production drops, leading to reduced red blood cell production and anemia of chronic disease. Clients may present with fatigue, pallor, and reduced oxygen-carrying capacity.

B. CKD is associated with hypocalcemia (low calcium levels) rather than increased calcium. This occurs because the kidneys are unable to convert vitamin D into its active form (calcitriol), which is necessary for calcium absorption in the intestines. In addition, phosphate retention occurs in CKD, and excess phosphate binds with calcium, further lowering serum calcium levels. Over time, this imbalance can lead to renal bone disease (renal osteodystrophy).

C. CKD commonly leads to metabolic acidosis, meaning bicarbonate levels are typically decreased, not increased. The kidneys are unable to excrete hydrogen ions effectively or regenerate sufficient bicarbonate to buffer acids. This results in acid buildup in the blood, which may contribute to symptoms such as fatigue, rapid breathing (Kussmaul respirations in severe cases), and bone demineralization.

D. Creatinine is a waste product generated from normal muscle metabolism and is excreted almost entirely by the kidneys. In CKD, the glomerular filtration rate (GFR) decreases, meaning the kidneys cannot effectively filter and eliminate creatinine. As a result, serum creatinine levels rise, making it one of the most important and reliable indicators of declining kidney function. Elevated creatinine often correlates with worsening CKD stage and is used alongside blood urea nitrogen (BUN) to monitor disease progression and renal impairment severity.