Pharmacologic class: Calcimimetic
Therapeutic class: Endocrine and metabolic agent
Pregnancy risk category C
Directly lowers parathyroid hormone (PTH) levels by increasing sensitivity of calcium-sensing receptors to extracellular calcium
Tablets: 30 mg, 60 mg, 90 mg
Indications and dosages
➣ Secondary hyperparathyroidism in patients with chronic renal disease who are on dialysis
Adults: Dosage individualized; recommended starting dosage is 30 mg P.O. daily. Measure serum calcium and phosphorus levels within 1 week and intact parathyroid hormone (iPTH) 1 to 4 weeks after initiation or dosage adjustment; titrate dosage no more often than every 2 to 4 weeks through sequential doses of 60 mg, 90 mg, 120 mg, and 180 mg P.O. once daily to recommended target iPTH for chronic renal disease patients on dialysis of 150 to 300 pg/ml.
➣ Hypercalcemia in patients with parathyroid carcinoma
Adults: Recommended starting dosage is 30 mg P.O. twice daily, titrated every 2 to 4 weeks through sequential doses of 60 mg and 90 mg twice daily, and 90 mg three or four times daily as needed to normalize serum calcium level.
• Decreased calcium or iPTH level
• Concurrent use or discontinuation of strong CYP3A4 inhibitors (such as erythromycin, itraconazole, or ketoconazole)
• Hypersensitivity to drug or its components
Use cautiously in:
• decreased serum calcium level, moderate or severe hepatic impairment
• pregnant or breastfeeding patients
• children (safety and efficacy not established).
• Don't initiate therapy if serum calcium level is less than lower limit of normal range (8.4 mg/dl).
• Administer tablets whole with food or shortly after a meal.
• If iPTH level decreases below recommended target range (150 to 300 pg/ml), reduce dosage of cinacalcet and vitamin D sterols or discontinue therapy.
• During titration, monitor serum calcium level frequently; if level drops below normal, take appropriate measures to increase it, such as providing supplemental calcium, initiating or increasing dosage of calcium-based phosphate binder or vitamin D sterols, or withholding cinacalcet temporarily.
• Adjust dosage and closely monitor iPTH and calcium levels if patient is receiving or discontinuing a strong CYP3A4 inhibitor.
CNS: dizziness, asthenia
GI: nausea, vomiting, diarrhea, anorexia
Other: chest pain (noncardiac)
Drug-drug. Amitriptyline: increased amitriptyline and nortriptyline (active metabolite) exposure
Drugs metabolized by CYP4502D6 (such as flecainide, thioridazine, most tricyclic antidepressants, vinblastine): increased blood levels of either drug
Ketoconazole and other strong CYP3A4 inhibitors: increased cinacalcet exposure
Drug-diagnostic tests. Calcium: decreased
• Closely monitor iPTH and serum calcium levels throughout therapy in patients with moderate to severe hepatic impairment and in those who start or discontinue therapy with strong CYP3A4 inhibitor.
• Monitor iPTH level carefully to ensure that it doesn't fall below 100 pg/ml because adynamic bone disease may develop.
• Measure serum calcium and phosphorus levels within 1 week and iPTH level 1 to 4 weeks after initiation or dosage adjustment. Once maintenance dosage is established, measure serum calcium and phosphorus levels approximately monthly and iPTH level every 1 to 3 months.
• Monitor serum calcium level closely in patient with history of seizure disorders.
• Instruct patient to take tablets whole with food or shortly after a meal.
• As appropriate, review all other significant adverse reactions and interactions, especially those related to the drugs and tests mentioned above.
Pharmacologic: calcimimetic agents
Time/action profile (effect on PTH levels)
|PO||rapid||2–6 hr||6–12 hr|
Adverse Reactions/Side Effects
Central nervous system
- nausea (most frequent)
- vomiting (most frequent)
Fluid and Electrolyte
- adynamic bone disease
Drug-Drug interactionInhibits CYP2D6 and may ↑ levels of flecainide, vinblastine, thioridazine, metoprolol, carvedilol, and most tricyclic antidepressants ; dose adjustments may be necessary.Blood levels are ↑ by strong CYP3A4 inhibitors including ketoconazole, itraconazole, and erythromycin ; monitoring and dose adjustment may be necessary.
- Monitor for signs and symptoms of hypocalcemia (paresthesias, myalgias, cramping, tetany, convulsions) during therapy. If calcium levels decrease to below normal, serum calcium may be increased by adjusting dose (see Lab Test Considerations) and providing supplemental serum calcium, initiating or increasing dose of calcium-based phosphate binder or vitamin D.
- Lab Test Considerations: Monitor serum calcium and phosphorous levels within 1 wk after initiation of therapy or dose adjustment and monthly for patients with hyperparathyroidism or every 2 mo for patients with parathyroid carcinoma once maintenance dose has been established, especially in patients with a history of seizure disorder. Therapy should not be initiated in patients with serum calcium less than the lower limit of normal (8.4 mg/dL).
- If serum calcium ↓ below 8.4 mg/dL but remains above 7.5 mg/dL, or if symptoms of hypocalcemia occur, use calcium-containing phosphate binders and/or vitamin D sterols to ↑ serum calcium. If serum calcium ↓ below 7.5 mg/dL, or if symptoms of hypocalcemia persist and the dose of vitamin D cannot be ↑, withhold administration of cinacalcet until serum calcium levels reach 8.0 mg/dL, and/or symptoms of hypocalcemia resolve. Re-initiate therapy using next lowest dose of cinacalcet.
- Monitor serum iPTH levels 1 to 4 wk after initiation of therapy or dose adjustment, and every 1 to 3 mo after maintenance dose has been established. If iPTH levels ↓ below 150–300 pg/mL, reduce dose or discontinue cinacalcet.
- Monitor liver function tests in patients with moderate to severe hepatic impairment during therapy.
Potential Nursing DiagnosesDeficient knowledge, related to medication regimen (Patient/Family Teaching)
- Cinacalcet may be used alone or in combination with vitamin D and/or phosphate binders.
- Oral: Administer with food or shortly after a meal. Take tablets whole, do not crush, break or chew.
- Instruct patient to take cinacalcet as directed.
- Advise patient to report signs and symptoms of hypocalcemia to health care professional promptly.
- Emphasize the importance of follow-up lab tests to monitor safely and efficacy.
- Decreased serum calcium levels.