Key Points
- Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
- Set objective targets and reassess frequently.
- Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.
Algorithm
- Stop causative meds; begin aggressive IV saline; correct electrolytes.
- Give calcitonin for rapid lowering; administer bisphosphonate or denosumab for sustained control.
- Monitor Ca, renal function, and symptoms; treat malignancy; plan outpatient bone‑modifying therapy.
Clinical Synopsis & Reasoning
Treat symptomatic or severe hypercalcemia with aggressive IV saline, calcitonin for rapid effect, and IV bisphosphonate (zoledronic acid/pamidronate) or denosumab for sustained control; stop exacerbating drugs and treat the underlying malignancy.
Treatment Strategy & Disposition
Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.
Epidemiology / Risk Factors
- Risk varies by comorbidity and precipitants; see citations for condition‑specific data.
Investigations
| Test | Role / Rationale | Typical Findings | Notes |
|---|
| Serum Ca (corrected/ionized), PTH, PTHrP, 25‑OH/1,25‑OH₂ D | Etiology | Humoral vs osteolytic vs vitamin D mediated | Guides therapy |
| Renal function and EKG | Complications | AKI, QT changes/arrhythmias | Monitor |
| Volume status assessment | Safety | Avoid fluid overload | Adjust rate |
High-Risk & Disposition Triggers
| Trigger | Why it matters | Action |
|---|
| Ca ≥14 mg/dL or symptoms (AMS, arrhythmia) | Life-threatening | Aggressive saline, calcitonin, IV bisphosphonate/denosumab; ICU if unstable |
| Renal failure or volume overload | Therapy limits | Loop diuretics after rehydration; nephrology consult |
| Underlying hematologic malignancy | TLS/osteolysis | Oncology plan; steroids in lymphoma/myeloma |
| Prolonged QT/arrhythmia | Cardiac risk | Telemetry |
| Immobility or thiazide/vitamin D intoxication | Worsening factors | Stop contributors |
Pharmacology
| Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations |
|---|
| Normal saline 200–300 mL/h (titrate) | Rehydration | Hours | Enhance calciuresis | Add loop diuretic after euvolemia |
| Calcitonin 4 IU/kg SC/IM q12h (up to q6h) | Rapid reducer | Hours | Quick but tachyphylaxis | Use for 48–72 h bridge |
| Zoledronic acid 4 mg IV (or Pamidronate 60–90 mg) or Denosumab 120 mg SC | Sustained control | Days | Inhibit bone resorption | Denosumab in renal failure |
Prognosis / Complications
- Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.
Patient Education / Counseling
- Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.
References
- ASCO/Endocrine Society guidance on hypercalcemia of malignancy — Link