Acyclovir, Inf/Oral
Antiviral, Systemic · Nucleoside analogue
Indications
Herpes simplex, varicella-zoster. See under dosage.
Dosage
ORAL: Herpes simplex treatment: Adults: 200 mg (400 mg in the immunocompromised or if absorption impaired) 5 times daily, usually for 5 days. Children: Under 2 yr, half adult dose; over 2 yr, same as adult dose. Herpes simplex, prevention of recurrence: Adults: 200 mg 4 times daily or 400 mg twice daily possibly reduced to 200 mg 2 or 3 times daily and interrupted every 6-12 mth. Herpes simplex, prophylaxis in the immunocompromised: Adults: 200-400 mg 4 times daily. Children: Under 2 yr, half adult dose; over 2 yr, same as adult dose. Varicella and herpes zoster, treatment: Adults: 800 mg 5 times daily for 7 days. Children: Varicella: 20 mg/kg (max 800 mg) 4 times daily for 5 days or under 2 yr, 200 mg 4 times daily; 2-5 yr, 400 mg 4 times daily; over 6 yr, 800 mg 4 times daily. IV INFUSION: Infusion over 1 hr. Herpes simplex or recurrent varicella-zoster: Adults: 5 mg/kg every 8 hr;…
Administration
Avoid rapid infusion; infuse over 1 hour to prevent renal damage; maintain adequate hydration; check for phlebitis and rotate infusion sites. Reconstitution: Reconstitute 500 mg with SWFI 10 mL. Do not use bacteriostatic water containing benzyl alcohol or parabens. For IV infusion dilute in D5W, D5NS, D5 1/4 NS, D5 ½ NS, LR, NS to a final concentration = 7 mg /mL. Compatibility: Stable in D5W, D5NS, D5 1/4 NS, D5 ½ NS, LR, NS. Y-site administration: Drug to Drug IV Compatibility: Amikacin, bumetanide, calcium gluconate, cephazolin, ceftriaxone, cimetidine, cisatracurium, dexamethasone, diphenhydramine, enalapril, famotidine, fentanyl, fluconazole, furosemide, gentamicin, heparin, hydrocortisone, hydromorphone, imipenem, insulin regular, linezolid, lorazepam, magnesium sulphate, methylprednisolone, metoclopramide, metronidazole, milrinone, nitroglycerin, propofol, ranitidine, tobramycin,…
Adverse Effects
Rash, photosensitivity, headache, dizziness, confusion, hallucinations, somnolence, convulsions. Rarely transient elevation of liver enzymes, blood urea and creatinine, acute renal failure, hepatitis, jaundice, decrease in haematological indices, pruritus, GI upset, fatigue, fever.
Risk Factor (Pregnancy/Lactation)
Pregnancy: No evidence of risk in humans. Lactation: Caution advised or effect undetermined. Precautions: Renal impairment. Maintain hydration. Elderly.
Interactions
Probenecid, cimetidine, mycophenolate mofetil, cyclosporin, tacrolimus, theophylline.
Advice to Patient
Take with or without meals. To prevent GI upset, take with meals. Contact prescriber if there is muscle pain, fever, acute headache, difficulty in urination, dark coloured urine, concentrated urine, constant lethargy, severe nausea or vomiting, rash, hallucinations, confusion, difficulty in breathing. Complete full course of therapy even if you feel better. Do not have sexual intercourse when visible lesions are present. Take sufficient amount of fluids (2-3 litres per day) to maintain hydration, unless restricted by the prescriber.
Pharmacokinetics
Absorption: Oral: Poorly absorbed; absorption improves with multiple small doses compared to one large daily dose. Metabolism: By viral enzymes and cellular enzymes. Bioavailability: Oral: 10%-20% with normal renal function (bioavailability decreases with increased dose). Half-life elimination: Terminal: Neonates and infants 3 mth: 3.8 ± 1.19 hrs. Infants >3 mth to Children 12 yrs: 2.36 ± 0.97 hrs. Adults: Approx. 2.5 hrs (with normal renal function); 20 hrs (ESRD); Haemodialysis: Approx. 5 hrs. Excretion: Urine (62%-91%).
Brands with this active ingredient
Compiled by Healify Pharmacy from published drug references. How we compile it →
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