Ganciclovir
Mechanism :
Ganciclovir is an acyclic nucleoside analogue of 2-deoxyguanosine that inhibits replication of herpes viruses. Ganciclovir has been shown to be active against cytomegalovirus (CMV) and herpes simplex virus (HSV) in human clinical studies.
Indication :
- Prevention of cytomegalovirus (CMV) disease in advanced HIV infection at risk for CMV disease
- Prevention of CMV disease in solid organ transplant recipients
- Treatment of CMV retinitis in immunocompromised patients
- Treatment of Congenital CMV
Contraindications :
Contraindicated in patients with hypersensitivity to ganciclovir or acyclovir. Ensure adequate hydration when using IV. Avoid in patients with neutrophil count <500 cell per microlitre. Regular-monitoring of white blood cell count is advised.
Dosing :
Congenital CMV:
6 mg/kg/dose twice a day intravenously every day for 6 weeks.
CMV disease and prophylaxis:
Induction:
10 mg/kg/24 hours IV divided into 2 doses given 12 hourly for 7-14 days followed by maintenance of 5-6 mg/kg/24 hours IV once daily.
Oral dose:For maintenance
30-90 mg/kg/day in 2 divided doses; Max 1000 mg/day.
Adverse Effect :
Neutropenia, thrombocytopenia, anemia, rash, abnormal LFTs, chills, edema, confusion ataxia, nervousness, paresthesia, psychosis, tremor, hypotension, hypertension, cardiac arrhythmias, gastrointestinal hemorrhage, eosinophilia, decreased blood glucose, alopecia, pruritus, urticaria, hematuria, increase in serum creatinine and urea.
Interaction :
Zidovudine: Since both zidovudine and ganciclovir have the potential to cause neutropenia and anemia, some patients may not tolerate concomitant therapy with these drugs at full dosage.
Probenecid: Renal clearance of ganciclovir decreased which is consistent with an interaction involving competition for renal tubular secretion.
Imipenem-cilastatin: Generalized seizures have been reported in patients who received ganciclovir and imipenem-cilastatin. These drugs should not be used concomitantly unless the potential benefits outweigh the risks.
Dapsone, Pentamidine, Flucytosine, Vincristine, Vinblastine, Adriamycin, Amphotericin B, Trimethoprim/Sulfamethoxazole Combinations or other Nucleoside Analogues: Drugs that inhibit replication of rapidly dividing cell populations such as bone marrow, spermatogonia and germinal layers of skin and gastrointestinal mucosa may have additive toxicity when administered concomitantly with ganciclovir. Therefore, such drugs, should be considered for concomitant use with ganciclovir only if the potential benefits are judged to outweigh the risks involved.
Renal Dose :
Dose in Renal Impairment GFR (mL/min)
Dose in Patients undergoing Renal Replacement Therapies
| CAPD | Dialysed. 1.25 mg/kg every day |
| HD | Dialysed. 1.25 mg/kg every day, given post dialysis on dialysis days |
| HDF/High flux | Dialysed. 1.25 mg/kg every day, given post dialysis on dialysis days |
| CAV/VVHD | Dialysed. 2.5 mg/kg per day |
Hepatic Dose :
No dosage adjustments are needed.