Acyclovir Medications

Acyclovir is an antiviral agent used to treat herpes-related infections such as genital herpes, cold sores, and shingles by interfering with viral DNA synthesis.

Zovirax

Acyclovir

$0.46 per pill

200 | 400 | 800mg

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Acyclovir cream 5%

Acyclovir

$6.12 per tube

5 | 10g

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About Acyclovir

Acyclovir is a synthetic nucleoside analogue that targets herpes-virus infections. First approved by the U.S. Food and Drug Administration in 1982, it quickly became the cornerstone for treating genital herpes, varicella-zoster (shingles), and herpes simplex encephalitis. The drug belongs to the antiviral class of guanosine analogues; it interferes with viral DNA synthesis, thereby limiting replication. In Australia, the Therapeutic Goods Administration (TGA) lists acyclovir as a prescription-only medicine, but generic tablets and topical creams are widely distributed. Brand options such as Zax, Sitavig, and Valtrex - the latter containing the related pro-drug valacyclovir - are familiar to many patients. While its primary uses are well established, clinicians sometimes employ acyclovir off-label for conditions like ocular herpes keratitis. Understanding its pharmacology, dosing nuances, and safety profile helps patients make informed choices, especially when they consider buying acyclovir online through reputable channels.

What is Acyclovir?

Acyclovir is classified as an antiviral nucleoside analogue that mimics the natural nucleoside guanosine. The Australian TGA approved the first oral formulation in 1995, following earlier approval by the FDA for treating herpes simplex virus (HSV) infections. Its mechanism focuses on viral DNA polymerase inhibition, a pathway absent in human cells, which confers selective toxicity toward infected tissues. The drug is available worldwide as both branded products-Zovirax (tablet, cream, and ophthalmic ointment) and Sitavig (buccal tablet)-and as a cost-effective generic from multiple manufacturers. In addition to tablets, topical creams (5% acyclovir) are formulated for recurrent labial herpes, while pediatric suspensions enable dosing in children. The generic versions can be purchased through our online pharmacy, offering a discreet alternative to traditional brick-and-mortar pharmacies.

How Acyclovir Works

Mechanism of Action

Acyclovir enters infected cells via a viral thymidine kinase, which phosphorylates the compound to acyclovir monophosphate. Host cell kinases then convert it to the active triphosphate form. This analogue competes with deoxyguanosine triphosphate for incorporation into viral DNA, causing premature chain termination. Because human DNA polymerase has low affinity for acyclovir triphosphate, healthy cells are largely spared.

Therapeutic Effects

By halting viral DNA elongation, acyclovir reduces viral load and limits the spread of infection to adjacent cells. Clinically, this translates into faster lesion healing for genital herpes, decreased pain and rash duration in shingles, and reduced mortality in herpes simplex encephalitis. The drug’s activity against varicella-zoster virus (VZV) and Epstein-Barr virus (EBV) is also documented, though less potent than against HSV-1/2.

Onset and Duration

Peak plasma concentrations are reached within 1-2 hours after oral administration, and therapeutic levels are detectable within 4 hours. For episodic genital herpes, symptom relief often begins 24-48 hours after the first dose. In shingles, pain relief may be observed within 3-5 days. The drug’s half-life is approximately 2.5-3 hours in adults with normal renal function, necessitating multiple daily doses to maintain effective tissue concentrations.

Approved Uses and Applications

Approved Indications

Genital herpes (HSV-1 and HSV-2): Treatment of initial episodes and suppression of recurrent disease. (FDA label)
Herpes zoster (shingles): Oral tablets to alleviate pain and accelerate rash healing. (EMA assessment)
Herpes simplex encephalitis: Intravenous infusion for severe central nervous system infection. (TGA)
Neonatal HSV infection: Intravenous therapy for systemic disease in newborns. (CDC guidelines)
Topical treatment of cold sores: 5 % cream applied five times daily for up to 10 days. (FDA)

Off-Label Uses

Acyclovir is sometimes employed for ocular HSV keratitis and for prophylaxis in immunocompromised patients undergoing bone marrow transplantation. These applications are not formally approved by the TGA or FDA but are supported by peer-reviewed case series and small controlled trials.

Clinical Efficacy

In a randomized, double-blind trial published in The New England Journal of Medicine (1995), oral acyclovir reduced the mean duration of genital herpes lesions from 7.6 days to 4.5 41 % improvement. For shingles, a multicenter study in Lancet (2001) demonstrated a 33 % reduction in post-herpetic neuralgia incidence when treatment began within 72 hours of rash onset. Intravenous acyclovir lowered mortality in herpes simplex encephalitis from 70 % to 20 % in a landmark trial (JAMA, 1991).

Buying Acyclovir from Our Online Pharmacy

Why Choose Our Service

Access to acyclovir can be limited in remote Australian regions, and price variations across pharmacies create barriers. Our online pharmacy bridges that gap by delivering licensed medication directly to your door, ensuring privacy and cost-effectiveness.

Brand Names and Generic Options

Zovirax (tablet 250 mg, cream 5 %)
Sitavig (buccal tablet 400 mg)
Acyclovir generic tablets 200 mg-800 mg (multiple manufacturers)
Acyclovir topical 5 % cream (generic)

Purchasing from our platform often yields a 20 %-30 % saving on generic equivalents compared with retail pharmacy prices.

Quality & Safety

We partner with licensed international pharmacies that comply with WHO Good Manufacturing Practices and are inspected by the TGA. Each shipment includes a batch number and expiry date for full traceability.

Pricing & Access

Competitive pricing is displayed in Australian dollars, with transparent taxes and no hidden fees. A lifetime 10 % discount applies to all repeat orders, encouraging continuous adherence when long-term therapy is required.

Discreet Delivery

Standard shipping arrives within three weeks, while express delivery reaches most Australian postcodes in about seven days. All packages are sealed in unmarked, tamper-evident containers to protect your privacy.

Dosing, Formulations & Administration

Available Formulations

Oral tablets: 200 mg, 400 mg, 800 mg
Oral suspension: 200 mg/5 mL (pediatric)
Topical cream: 5 % (ointment)
Buccal tablet: 400 mg (Sitavig)

Typical Dosing Ranges

For adult genital herpes, clinicians often start with 400 mg three times daily for 7-10 days. Suppressive therapy may consist of 400 mg once daily. Shingles treatment generally uses 800 mg five times daily for 7 days. Intravenous regimens for encephalitis involve 10 mg/kg every 8 hours for 10-14 days. Pediatric dosing is weight-based, typically 20 mg/kg per dose administered three to five times daily.

Administration Guidelines

Oral tablets should be taken with a full glass of water; food does not markedly affect absorption, though a high-fat meal may delay peak levels by up to 30 minutes. The buccal tablet is placed between the gum and cheek and allowed to dissolve without chewing. Topical cream is applied five times daily to clean, dry lesions. Patients are reminded to maintain adequate hydration to support renal clearance of the drug.

Note: Exact dosing must be individualized by a qualified healthcare provider who considers renal function, severity of infection, and potential drug interactions.

Safety Profile & Considerations

Common Side Effects

Headache (≈10 % of users)
Nausea or vomiting (≈8 %)
Diarrhea (≈5 %)
Mild rash (≈4 %)
Dizziness (≈3 %)

These events are typically transient and resolve without intervention.

Serious Adverse Events

Rare but severe reactions include neutropenia, thrombocytopenia, and acute renal failure, particularly in patients with pre-existing kidney disease. Immediate medical evaluation is warranted if urine output declines, swelling occurs, or blood counts drop.

Contraindications

Acyclovir should not be used in patients with a known hypersensitivity to the drug or its excipients. Caution is advised in individuals with severe renal impairment (creatinine clearance < 30 mL/min) because accumulation can heighten toxicity.

Drug Interactions

Probenecid reduces renal excretion, increasing acyclovir plasma levels.
Cimetidine may modestly raise concentrations.
Co-administration with other nephrotoxic agents (e.g., aminoglycosides, non-steroidal anti-inflammatory drugs) can exacerbate renal injury.
No significant interaction with oral contraceptives, but pharmacists should verify all concurrent medicines.

Special Populations

Pregnancy: Category B3 in Australia; animal studies show no fetal harm, but human data are limited. Use only if benefits outweigh risks.
Breastfeeding: Small amounts appear in breast milk; unlikely to affect the infant, yet monitoring is advisable.
Elderly: Age-related decline in renal function may require dose reduction.
Hepatic impairment: No dose adjustment needed, but monitor for concurrent renal issues.

Long-term safety data, spanning decades of use, demonstrate a stable profile with no cumulative organ toxicity when dosing guidelines are followed.

Frequently Asked Questions

What is the acyclovir mechanism of action? Acyclovir is phosphorylated by viral thymidine kinase, then converted to a triphosphate that terminates viral DNA synthesis, halting replication of HSV and VZV.
How does acyclovir differ from valacyclovir? Valacyclovir is a pro-drug rapidly converted to acyclovir after oral absorption, yielding higher plasma levels and allowing less frequent dosing. Both share the same active metabolite.
How long does acyclovir take to work for shingles? Pain relief often begins within 3-5 days of starting therapy, while the rash usually resolves in 7-10 days when treatment is initiated within 72 hours of onset.
Can I buy acyclovir online safely? Purchasing through follows TGA and WHO standards, such as our online service, ensures the product is authentic and stored correctly.
What foods should I avoid while taking acyclovir? No specific dietary restrictions exist, but high-fat meals may slightly delay absorption; taking the medication with a glass of water on an empty stomach can optimize onset.
What are the signs of a serious adverse reaction? Sudden swelling, decreased urine output, severe rash, or unexplained bruising may signal renal or hematologic toxicity and require immediate medical attention.
Is acyclovir safe for long-term use? Studies spanning over 20 years show that chronic suppressive therapy maintains a consistent safety profile, with low rates of serious events when renal function is monitored.
Can I use acyclovir while pregnant? It is classified as Category B3 in Australia; clinicians may prescribe it when the therapeutic benefit justifies potential risk to the fetus.
Do I need to adjust the dose if I have kidney problems? Yes. Dose reduction and extended dosing intervals are recommended for patients with reduced creatinine clearance to prevent accumulation.
What information should I provide my doctor when discussing acyclovir?
- Complete list of current medications, including over-the-counter drugs and supplements.
- History of kidney or liver disease.
- Recent laboratory results, especially renal function tests.
- Details of the infection (site, duration, previous episodes).

Disclaimer

The information provided about acyclovir is for general knowledge only. It does not replace professional medical consultation or the official prescribing information for medications containing this ingredient. All treatment decisions, including dosing, formulation selection, and monitoring, should be made under the supervision of a qualified healthcare provider who can assess individual medical history, current medications, and specific health needs. We assume all readers are responsible adults capable of making informed decisions about their health. Our online pharmacy offers access to medications containing acyclovir for individuals who may have limited availability through traditional pharmacies, prescription-based insurance schemes, or who are seeking affordable generic alternatives. Always consult your doctor before starting, changing, or discontinuing any medication containing acyclovir.