Ganciclovir

What ganciclovir is and how it works

Ganciclovir is a prescription-only intravenous antiviral medicine used to treat and prevent cytomegalovirus (CMV) disease -- a viral infection that can cause serious eye, lung, and other organ disease in people with weakened immune systems, such as those with AIDS, organ or bone marrow transplant recipients, or people on chemotherapy. (1)

Ganciclovir is given by slow intravenous infusion in a hospital or closely supervised setting, never as a rapid injection or into a muscle. It carries a boxed warning -- the FDA's strongest safety warning -- covering serious blood-cell effects, and, based on animal studies, effects on fertility, the potential for birth defects, and the potential to cause cancer. Your care team will monitor your blood counts closely and discuss contraception requirements with you before and during treatment.

Mechanism of action: how ganciclovir works

Ganciclovir is a synthetic nucleoside analogue of 2'-deoxyguanosine that inhibits replication of herpesviruses, including cytomegalovirus (CMV), in vitro and in vivo. It is phosphorylated intracellularly to ganciclovir triphosphate, which inhibits viral DNA polymerase and is incorporated into viral DNA, terminating or slowing further DNA elongation. (1) (3)

What ganciclovir is used for

Before taking ganciclovir

Do not take / not appropriate for

• Do not receive ganciclovir if you have had an allergic reaction to ganciclovir, valganciclovir, or aciclovir/valaciclovir -- cross-hypersensitivity between these medicines is possible due to their similar chemical structure. (all confirmed markets) (1) (3)
• Ganciclovir is not indicated for congenital or neonatal CMV disease, or for CMV infection in people who are not immunocompromised. (New Zealand, Canada) (5) (3)
• Do not breastfeed while receiving ganciclovir. (United Kingdom) (2)

Tell your clinician about

• Whether you or your partner may become pregnant -- effective contraception is required for women during treatment and for at least 30 days afterward, and barrier contraception for men during treatment and for at least 90 days afterward.
• Any plans for a family -- ganciclovir may temporarily or permanently reduce sperm production and fertility, based on animal studies.
• Any kidney problems, since your dose depends on kidney function.
• Any low blood counts or bleeding problems.
• All other medicines you take, especially imipenem-cilastatin, didanosine, zidovudine, probenecid, ciclosporin, amphotericin B, or other medicines that affect the kidneys or bone marrow.
• Whether you are already, or may be, pregnant -- pregnancy testing is recommended before starting treatment for women who could become pregnant.

How to take ganciclovir

• Given only by slow intravenous infusion over 1 hour, by a healthcare professional, into a vein with adequate blood flow.
• Must NEVER be given as a rapid or bolus IV injection, or by intramuscular or subcutaneous injection -- this can cause severe tissue irritation and increased toxicity due to the solution's high pH.
• You will have regular blood tests (complete blood count, including platelets) before and throughout treatment.
• Your dose is individualised based on your kidney function, weight, and clinical response -- do not attempt to adjust it yourself.

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5) (6)

Missed dose

Because ganciclovir is given by a healthcare professional on a scheduled infusion program, a missed dose is managed directly by your care team rather than something to self-manage at home.

Overdose

Because ganciclovir is administered by a healthcare professional, any concern about an incorrect dose is identified and managed by the treating team. Overdose has been associated with increased toxicity, particularly to the bone marrow and kidneys; seek immediate medical attention if an overdose is suspected. (3)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Serious warnings

Interactions

• Didanosine: ganciclovir can substantially increase didanosine levels (38-67% AUC increase) -- monitor closely for didanosine toxicity. (1) (2)
• Zidovudine: combined use has the potential to cause neutropenia and anaemia -- monitor white blood cell counts with differential and haemoglobin levels frequently. (1)
• Probenecid: may reduce ganciclovir clearance and increase levels -- monitor for evidence of ganciclovir toxicity. (1)
• Imipenem-cilastatin: generalised seizures have been reported with concomitant use. (1)
• Ciclosporin or amphotericin B: monitor renal function closely. (1)
• Other medicines that can affect bone marrow (such as dapsone, pentamidine, flucytosine, vincristine, vinblastine, adriamycin, amphotericin B, trimethoprim/sulfamethoxazole combinations) or other nucleoside analogues should be combined with ganciclovir only if the potential benefit outweighs the risk. (1)

Pregnancy, breastfeeding, kidney/liver function, age

Monitoring

Before starting

• Complete blood count (including platelets) and haemoglobin
• Kidney function (creatinine clearance)
• Pregnancy test for women of reproductive potential
• Review of other medicines for interactions

During treatment

• Frequent complete blood counts with differential and platelet counts.
• Kidney function monitoring, particularly in elderly patients or those on other nephrotoxic medicines.
• Monitoring for signs of infection, unusual bleeding, or bruising.
• Ongoing contraception use throughout treatment and for the required period afterward.
• Monitoring for new visual symptoms in patients being treated for CMV retinitis.

Storage

Stored, reconstituted, and prepared by pharmacy/hospital staff according to the product's specific storage and handling requirements (including precautions for handling a cytotoxic/potentially carcinogenic agent); not self-stored by patients at home.

Frequently asked questions

References

1. GANCICLOVIR INJECTION, for intravenous use -- full prescribing information (label revised 02/2017, accessdata document 209347lbl.pdf)U.S. Food and Drug Administration, accessdata.fda.gov full prescribing information · United States · accessed 2026-07-30 · source 1
2. Ganciclovir 500 mg Powder for solution for infusion vial -- Summary of Product Characteristics (SmPC, dated 30/07/2025)UK Medicines and Healthcare products Regulatory Agency / electronic medicines compendium (emc), Summary of Product Characteristics · United Kingdom · accessed 2026-07-30 · source 2
3. GANCICLOVIR FOR INJECTION (500 mg/vial), Product Monograph, dated 12 April 2023Health Canada -- Formative Pharma Inc., product monograph · Canada · accessed 2026-07-30 · source 3
4. Ganciclovir injection -- ARTG registrations (Cymevene 500mg ARTG 10047, Ganciclovir Agila 500mg ARTG 233583)Australian Therapeutic Goods Administration (TGA), Australian Register of Therapeutic Goods (ARTG) · Australia · accessed 2026-07-30 · source 4
5. Cymevene 500 mg powder for intravenous infusion -- New Zealand Data Sheet (DS 181120)New Zealand Medicines and Medical Devices Safety Authority (Medsafe) · New Zealand · accessed 2026-07-30 · source 5
6. Cymevene IV (INN: ganciclovir) -- Article 30 referral, harmonisation of product information across EU member states (11 April 2016)European Medicines Agency (EMA) -- Committee for Medicinal Products for Human Use (CHMP) · European Union · accessed 2026-07-30 · source 6

Brand names by country

Single-ingredient ganciclovir names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries