Action and Spectrum

Actions and spectrum: 

ganciclovir is an antiviral medication that belongs to the class of synthetic nucleoside analogs. It is structurally like guanine and interferes with viral DNA synthesis by inhibiting viral DNA polymerase.

ganciclovir is active against a broad spectrum of herpesviruses, including cytomegalovirus (CMV), herpes simplex virus types 1 and 2, and Epstein-Barr virus. 

ganciclovir is primarily used for the treatment and prophylaxis of cytomegalovirus (CMV) infections, especially in immunocompromised patients, such as those with HIV, organ transplant recipients, or patients undergoing chemotherapy. 

Drug Interaction

Adverse Reaction

Frequency defined 

>10% 

Thrombocytopenia (20%) 

Neutropenia (25-50%) 

1-10% 

Elevated LFTs 

Confusion 

Nausea/vomiting 

Paresthesia 

Retinal detachment 

Sepsis 

Anemia 

Headache 

Neuropathy 

Pruritus 

Rash 

Weakness  

Frequency not defined 

Cardiac disorders: Arrhythmias 

Eye disorders: vitreous disorders, conjunctivitis, Visual impairment, macular edema 

General disorders: Fatigue, edema, malaise, chest pain, pain, asthenia. 

Investigations: abnormal hepatic function, increased alanine aminotransferase, increased Blood alkaline phosphatase. 

connective tissue and Musculoskeletal disorders: Back pain, muscle spasms, myasthenia, myalgia, leg cramps, arthralgia 

Psychiatric disorders: confusional state, agitation, thinking abnormal, Depression, anxiety, psychotic disorder, abnormal dreams 

Respiratory, mediastinal, and thoracic disorders: dyspnea, Cough 

Vascular disorders: Hypertension, vasodilation, Hypotension, phlebitis 

Lymphatic and blood disorders: bone marrow failure, Pancytopenia 

Labyrinth and Ear disorders: ear pain, Tinnitus, deafness 

Gastrointestinal disorders: dyspepsia, mouth ulceration, abdominal distention, gastrointestinal perforation, dry mouth. 

Nutrition and Metabolism disorders: Weight decreased 

Nervous system disorders: insomnia, hypoaesthesia, somnolence, tremor, Headache, dizziness, paresthesia, seizures, dysgeusia 

Urinary and Renal disorders: renal function abnormal, hematuria, Kidney failure, urinary frequency    

Post marketing Reports 

Congenital anomaly 

Cataracts, dry eyes 

Cholelithiasis, hepatic failure, cholestasis, hepatitis 

increased Blood triglycerides 

Dysesthesia, extrapyramidal disorder, amnesia, myelopathy, third cranial nerve paralysis, encephalopathy, dysphasia, facial paralysis, anosmia, intracranial hypertension 

Renal tubular disorder  

Bronchospasm 

Stevens Johnson syndrome, Exfoliative dermatitis, Peripheral ischemia 

Hemolytic anemia, granulocytopenia, agranulocytosis 

torsade de pointes, Cardiac arrest, tachycardia 

Intestinal ulcer 

allergic reaction, Anaphylactic reaction, vasculitis 

hypercalcemia, rhabdomyolysis, Acidosis, hyponatremia Arthritis 

Hallucinations, Irritability 

testicular hypotrophy, Infertility 

Black Box Warning

Black Box Warning: 

ganciclovir has a black box warning for hematological toxicity, including granulocytopenia, anemia, and thrombocytopenia. ganciclovir can also cause serious and potentially fatal infections, especially in immunocompromised patients, and should only be used in patients with cytomegalovirus (CMV) retinitis or CMV prophylaxis in immunocompromised patients. 

Contraindication / Caution

Contraindication/Caution: 

Contraindication: 

ganciclovir is contraindicated in patients who have a history of clinically significant hypersensitivity to ganciclovir or any component of the formulation. It is also contraindicated in patients with low neutrophil count (less than 500 cells/mm³) or a severely low platelet count (less than 25,000 cells/mm³).  

Caution: 

• Hematologic Toxicity: ganciclovir can cause hematologic toxicity, including neutropenia, thrombocytopenia, and anemia. Therefore, it is necessary to monitor blood counts regularly. 
• Renal Toxicity: ganciclovir is excreted primarily by the kidneys, and it can cause renal toxicity. Patients with pre-existing renal impairment should be monitored closely when taking this medication. 
• Hepatic Toxicity: ganciclovir can cause hepatotoxicity, and liver function tests should be monitored regularly. 
• Neurological Toxicity: ganciclovir can cause seizures, tremors, and other neurological symptoms. Patients with pre-existing neurological conditions should be closely monitored when taking this medication. 
• Teratogenicity: ganciclovir is teratogenic and can cause birth defects.  
• Immunodeficiency: ganciclovir can cause immunosuppression and increase the risk of opportunistic infections, including cytomegalovirus (CMV) disease. Patients with HIV infection or other immunodeficiency disorders should be monitored closely when taking this medication.

Comorbidities: 

ganciclovir is an antiviral drug that is primarily used to treat cytomegalovirus (CMV) infection. It is used in patients with weakened immune systems, such as those with HIV/AIDS or organ transplant recipients, who are at a higher risk of developing CMV infections. Patients with kidney or liver disease may require dosage adjustments or monitoring when taking ganciclovir.

ganciclovir in patients with pre-existing bone marrow suppression should be given with caution, as it may cause further suppression of the bone marrow. It may also cause gastrointestinal, renal, and central nervous system side effects, which should be monitored in patients with pre-existing conditions affecting these systems. 

Pregnancy / Lactation

Pregnancy consideration: US FDA pregnancy category Not Assigned 

Lactation: ganciclovir is excreted in human milk  

Pregnancy category: 

• Category A: Satisfactory and well-controlled studies show no risk to the fetus in the first or later trimester. 
• Category B: There is no evidence of risk to the fetus found in animal reproduction studies and there are not enough studies on pregnant women. 
• Category C: Adverse effects on the fetus found with evidence in animal reproduction studies and no adequate evidence for an effect in humans, care must be taken for potential risks in pregnant women. 
• Category D: There is adequate data available with sufficient evidence of human fetal risk from various platforms, but despite potential risks may be used only in emergency cases for potential benefits. 
• Category X: Drugs listed in this category outweigh risks over benefits These category drugs should be prohibited for pregnant women. 
• Category N: There is no data available for the drug under this category. 

Pharmacology

Pharmacology: 

ganciclovir is an antiviral drug that works by inhibiting viral DNA synthesis. It is a synthetic analog of 2′-deoxyguanosine, which becomes phosphorylated intracellularly by the viral protein kinase encoded by human cytomegalovirus (HCMV), forming ganciclovir triphosphate. ganciclovir triphosphate competes with the natural substrate, 2′-deoxyguanosine triphosphate, for incorporation into viral DNA by viral DNA polymerase.

Once incorporated into the viral DNA, ganciclovir triphosphate inhibits further elongation of the DNA strand, leading to the termination of viral DNA synthesis. ganciclovir is active against several herpesviruses, including HCMV, herpes simplex virus (HSV), and varicella-zoster virus (VZV). It is also active against Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6).  

Pharmacodynamics: 

ganciclovir is a synthetic nucleoside analog that is phosphorylated by the virus-encoded kinase to produce ganciclovir triphosphate. ganciclovir triphosphate competes with the natural nucleoside triphosphates for incorporation into the replicating viral DNA, resulting in chain termination and inhibition of viral DNA synthesis.

ganciclovir also inhibits the viral DNA polymerase and induces DNA strand breaks. ganciclovir exhibits antiviral activity against herpes simplex virus (HSV), cytomegalovirus (CMV), and Epstein-Barr virus (EBV). It is most used for the prevention and treatment of CMV infections, particularly in immunocompromised patients.  

Pharmacokinetics: 

Absorption 

ganciclovir is administered intravenously, achieving complete bioavailability. After administration, the drug is rapidly distributed in the plasma and tissues. 

Distribution 

ganciclovir has a large volume of distribution, and it penetrates various tissues, including the cerebrospinal fluid. ganciclovir readily crosses the placenta, and low levels of the drug have been found in breast milk. 

Metabolism 

ganciclovir undergoes minimal hepatic metabolism, with approximately 90% of the drug being excreted unchanged in the urine. 

Elimination and excretion 

ganciclovir is primarily eliminated by the kidneys via glomerular filtration and active tubular secretion. The plasma half-life of ganciclovir in patients with normal renal function ranges from 2.5 to 5 hours. The drug is removed from the body by dialysis. 

Adminstartion

Administration: 

ganciclovir is available in several forms, including intravenous (IV) injection, oral capsules, and ophthalmic gel. For the treatment of CMV retinitis in immunocompromised patients, ganciclovir is given by slow IV infusion over one hour or through a surgically implanted catheter into a large central vein.

The duration and dose of treatment depend on the patient’s weight, renal function, and severity of the infection. For the prevention of CMV disease in transplant patients, ganciclovir may be given orally or IV, depending on the patient’s condition and the prescribing physician’s preference. For ophthalmic use, ganciclovir is available as a gel, which is applied to the affected eye(s) every three hours while awake. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: ganciclovir 

Pronounced: [ gan-SYE-kloe-veer]  

Why do we use ganciclovir? 

• Cytomegalovirus (CMV) retinitis in immunocompromised patients, such as those with AIDS 
• CMV prophylaxis in transplant recipients 
• Prevention of CMV infection in bone marrow transplant recipients 
• Treatment of CMV gastroenteritis and colitis 
• Treatment of congenital CMV infection in infants <