Can Ganciclovir Cause Hypercalcemia?
Ganciclovir does not typically cause hypercalcemia, and this is not a recognized adverse effect in clinical guidelines or standard monitoring protocols. The principal dose-limiting toxicity of ganciclovir is myelosuppression, not electrolyte disturbances 1.
Primary Adverse Effects of Ganciclovir
The well-established side effects of ganciclovir are:
- Bone marrow suppression is the major dose-limiting toxicity, requiring dose reduction or interruption in up to 40% of patients due to hematologic toxicity 1
- Neutropenia occurs frequently and may necessitate treatment with granulocyte colony-stimulating factor 1, 2
- Renal toxicity manifested as increased serum creatinine, which may require dose modification 1
- Elevated liver enzymes, though these occur less frequently than bone marrow suppression 1
Evidence Regarding Hypercalcemia
There is only one isolated case report from 1998 describing ganciclovir-associated hypercalcemia in a renal transplant patient 3. This single case report noted:
- Hypercalcemia occurred with low serum parathormone (PTH) levels 3
- There was an increase in 1,25 dihydroxy vitamin D concentrations 3
- The mechanism remained unclear and unexplained 3
This represents an extremely rare and poorly understood association that has not been reproduced in the literature or incorporated into clinical monitoring guidelines.
Standard Monitoring Recommendations
Guidelines recommend monitoring for ganciclovir's known toxicities:
- Complete blood counts should be monitored twice weekly during induction therapy and once weekly during maintenance therapy 1
- Renal function should be monitored regularly as renal toxicity can occur and may require dose adjustment 1
- Calcium monitoring is not part of standard ganciclovir surveillance protocols 4, 1
Clinical Bottom Line
Hypercalcemia is not a recognized complication of ganciclovir therapy in clinical practice. If hypercalcemia occurs in a patient receiving ganciclovir, alternative etiologies should be thoroughly investigated, including malignancy, hyperparathyroidism, vitamin D toxicity, immobilization, or other medications (particularly calcium-containing phosphate binders if the patient has renal disease) 5.