Acyclovir (Acyclovir) - Side Effects and Adverse Reactions

ADVERSE REACTIONS

The adverse reactions listed below have been observed in controlled and uncontrolled clinical trials in approximately 700 patients who received acyclovir at ~5 mg/kg (250 mg/m²) 3 times daily, and approximately 300 patients who received ~10 mg/kg (500 mg/m²) 3 times daily.

The most frequent adverse reactions reported during administration of acyclovir were inflammation or phlebitis at the injection site in approximately 9% of the patients, and transient elevations of serum creatinine or BUN in 5% to 10% (the higher incidence occurred usually following rapid [less than 10 minutes] intravenous infusion). Nausea and/or vomiting occurred in approximately 7% of the patients (the majority occurring in nonhospitalized patients who received 10 mg/kg). Itching, rash, or hives occurred in approximately 2% of patients. Elevation of transaminases occurred in 1% to 2% of patients.

The following hematologic abnormalities occurred at a frequency of less than 1%: anemia, neutropenia, thrombocytopenia, thrombocytosis, leukocytosis, and neutrophilia. In addition, anorexia and hematuria were observed.

Observed During Clinical Practice

In addition to adverse events reported from clinical trials, the following events have been identified during post-approval use of acyclovir injection in clinical practice. Because they are reported voluntarily from a population of unknown size, estimates of frequency cannot be made. These events have been chosen for inclusion due to either their seriousness, frequency of reporting, potential causal connection to acyclovir or a combination of these factors.

General: Anaphylaxis, angioedema, fatigue, fever, headache, pain and peripheral edema.

Digestive: Abdominal pain, diarrhea, gastrointestinal distress, nausea.

Cardiovascular: Hypotension.

Hematologic and Lymphatic: Disseminated intravascular coagulation, hemolysis, leukocytoclastic vasculitis, leukopenia, lymphadenopathy.

Hepatobiliary Tract and Pancreas: Elevated liver function tests, hepatitis, hyperbilirubinemia, jaundice.

Musculoskeletal: Myalgia.

Nervous: Aggressive behavior, agitation, ataxia, coma, confusion, delirium, dizziness, dysarthria, encephalopathy, hallucinations, obtundation, paresthesia, psychosis, seizure, somnolence, tremor. These symptoms may be marked, particularly in older adults (see PRECAUTIONS).

Skin: Alopecia, erythema multiforme, photosensitive rash, pruritus, rash, Stevens-Johnson syndrome, toxic epidermal necrolysis, urticaria. Severe local inflammatory reactions, including tissue necrosis, have occurred following infusion of acyclovir into extravascular tissues.

Special Senses: Visual abnormalities.

Urogenital: Renal failure, elevated blood urea nitrogen, elevated creatinine (see WARNINGS).

REPORTS OF SIDE EFFECTS / ADVERSE REACTIONS RELATED TO ACYCLOVIR

Possible Acyclovir side effects / adverse reactions in 36 year old female

Reported by a consumer/non-health professional from United States on 2007-01-08

Patient: 36 year old female

Reactions: CD4 Lymphocytes Decreased, Squamous Cell Carcinoma, Drug Ineffective

Adverse event resulted in: life threatening event, disablity

Suspect drug(s):
Acyclovir

Possible Acyclovir side effects / adverse reactions in 45 year old male

Reported by a pharmacist from United States on 2007-01-11

Patient: 45 year old male weighing 84.4 kg (185.6 pounds)

Reactions: Renal Tubular Disorder, Renal Failure Acute

Adverse event resulted in: hospitalization

Suspect drug(s):
Acyclovir

Other drugs received by patient: Acetaminophen; Dextrose; Glucagon; Ibuprofen; Regular Insulin; Sodium Chloride; Potassium Chloride; Promethazine; Sennosides; Temazepam

Possible Acyclovir side effects / adverse reactions in 62 year old female

Reported by a pharmacist from United States on 2007-01-16

Patient: 62 year old female weighing 113.0 kg (248.6 pounds)

Reactions: Neurotoxicity, Restlessness, Nephropathy Toxic, Blood Creatinine Increased, Cerebral Haematoma, Delusion

Suspect drug(s):
Acyclovir