Valganciclovir

A to Z Drug Facts

Valganciclovir

	Action
	Indications
	Contraindications
	Route/Dosage
	Interactions
	Lab Test Interferences
	Adverse Reactions
	Precautions
Patient Care Considerations
	Administration/Storage
	Assessment/Interventions
	Patient/Family Education

(val-gan-sye-kloh-veer)

Valcyte

Class: Antiviral agent Action

Action Valganciclovir is a prodrug of ganciclovir, which inhibits cytomegalovirus (CMV) replication by inhibition of viral DNA synthesis.

Indications Treatment of CMV retinitis in patients with acquired immunodeficiency syndrome (AIDS).

Contraindications Hypersensitivity to ganciclovir or valganciclovir.

Route/Dosage

ADULTS: PO 900 mg twice/day for 21 days. Decreased Renal Function. ADULTS: PO Induction: 900 mg twice/day (creatinine clearance > 60 mL/min); 450 mg twice/day (creatinine clearance 40 to 59 mL/min); 450 mg Once/day (creatinine clearance 25 to 39 mL/min); 450 mg q 2 days (creatinine clearance 10 to 24 mL/min). Maintenance: 900 mg daily (creatinine clearance > 60 mL/min); 450 mg once/day (creatinine clearance 40 to 59 mL/min); 450 mg q 2 days (creatinine clearance 25 to 39 mL/min); 450 mg twice/wk (creatinine clearance 10 to 24 mL/min).

Interactions

Interaction studies have not been conducted; however, since valganciclovir is converted to ganciclovir, interactions associated with ganciclovir are expected to occur for valganciclovir. Amphotericin B, Cyclosporine, Nephrotoxic drugs: May increase serum creatinine. Cytotoxic drugs: May increase the risk of toxicity. Didanosine: Plasma levels of didanosine may be increased, while didanosine may decrease levels of ganciclovir. Imipenem-cilastatin: May cause generalized seizures. Probenecid: May reduce renal clearance and increase serum levels of ganciclovir. Zidovudine: Both ganciclovir and zidovudine can cause granulocytopenia.

Lab Test Interferences None well documented.

Adverse Reactions

CNS: Headache; insomnia; peripheral neuropathy; paresthesia; convulsions; psychosis; hallucinations; confusion; agitation. Retinal detachment. GI: Diarrhea; nausea; vomiting abdominal pain. GU: Decreased creatinine clearance. Neutropenia; anemia; thrombocytopenia; pancytopenia; bone marrow depression; aplastic anemia. OTHER: Catheter-related infection; fever; local and systemic infections and sepsis; hypersensitivity.

Precautions

Pregnancy: Category C. Lactation: Undermined; however, the Centers for Disease Control and Prevention recommends that HIV-infected mothers not breastfeed their infants to avoid risk of HIV transmission. Children: Safety and efficacy not established. Carcinogenesis: Valganciclovir is potentially carcinogenic. Cytopenia: Severe leukopenia, neutropenia, anemia, thrombocytopenia, bone marrow depression, and aplastic anemia have been reported; therefore, use with caution in patients with preexisting cytopenias, or who have received or are receiving myelosuppressive drugs or irradiation. Renal impairment: Use with caution and adjust dosage.

PATIENT CARE CONSIDERATIONS

Administration/Storage

Administer with food.
Patient should swallow tablet whole; do not crush, break, split or chew tablets.
If broken or crushed tablet comes in contact with skin or mucus membranes wash thoroughly with soap and water, and rinse eyes thoroughly with plain water.
Administer reduced dose to patient with renal impairment.
Store at controlled room temperature.

Assessment/Interventions

Obtain patient history, including drug history and any known allergies.
Note history of cytopenia or impaired renal function.
Ensure that baseline CBC and serum creatinine are determined before starting therapy and periodically during therapy.
Do not administer to patient if absolute neutrophil count is < 500/mm³, platelet count is < 25,000/mm³ or hemoglobin is < 8 gm/dL.

OVERDOSAGE: SIGNS & SYMPTOMS
	Pancytopenia, bone marrow depression, medullary aplasia, leukopenia, neutropenia, granulocytopenia, hepatitis, liver function disorder, worsening of hematuria, acute renal failure, elevated creatinine, abdominal pain, diarrhea, vomiting, generalized tremor, convulsion

Patient/Family Education

Explain name, dose, action and potential side effects of drug.
Warn patient that valganciclovir capsules cannot be substituted for ganciclovir tablets on a one-to-one basis.
Review dosing schedule with patient: 2 tablets bid for 21 days for induction then 2 tablets qd for maintenance.
Instruct patient to take each dose with food.
Advise patient to not chew, crush, break or split tablets. If direct contact with broken or crushed tablets occurs advise patient to wash thoroughly with soap and water, and to rinse eyes thoroughly with plain water.
Advise patient that this drug is not a cure for CMV retinitis and that they may continue to experience progression of retinitis during or following treatment.
Advise patient that valganciclovir is converted to ganciclovir in the body and that it may cause infertility and birth defects. Advise male patients to use barrier contraception and female patients to use effective contraception during and for at least 90 days following treatment.
Advise male patients that drug may cause temporary or permanent infertility.
Advise patient that drug may cause sedation, dizziness and/or confusion and to use caution while performing tasks requiring alertness, including driving and operating machinery.
Advise patient to immediately report any of the following to their health care provider: fever or other signs of infection, sore throat, unusual bruising or bleeding.
Advise patient that diarrhea, nausea, vomiting and headache are common side effectsand to inform their health care provider if they occur and are intolerable.
Instruct female patients to notify their health care provider if they become pregnant, plan on becoming pregnant, or are breastfeeding.
Instruct patient to not take any prescription or OTC medications or dietary supplements unless advised to do so by their health care provider.
Remind patient that office visits, ophthalmic examinations and laboratory tests will be required to monitor therapy and to be sure to keep appointments.