Acyclovir (Zovirax) Drug Information PDF

Overview of the Drug Class **Prototype: acyclovir (Zovirax) ** - **Category**: Antiviral Agent  - **Primary Function**: Acyclovir is used to treat infections caused by the herpesvirus family, including herpes simplex viruses (HSV), varicella-zoster virus (VZV), and, to a lesser extent...

Overview of the Drug Class **Prototype: acyclovir (Zovirax) ** - **Category**: Antiviral Agent  - **Primary Function**: Acyclovir is used to treat infections caused by the herpesvirus family, including herpes simplex viruses (HSV), varicella-zoster virus (VZV), and, to a lesser extent, cytomegalovirus (CMV).  - **Unique Features**: Acyclovir specifically targets viral DNA synthesis, minimizing effects on human cells.  Mechanism of Action - Acyclovir inhibits viral DNA synthesis by undergoing activation to acyclo−guanosine monophosphate (GMP) via the thymidine kinase enzyme. GMP is then converted to acyclo−guanosine triphosphate (GTP) which then inhibits viral DNA polymerase and gets incorporated into viral DNA, blocking further DNA chain growth.  Indications and Therapeutic Uses - **Herpes Simplex Virus**: Acyclovir is the treatment of choice for primary and recurrent mucocutaneous herpes simplex infections, including oral and genital herpes, by reducing the duration and severity of outbreaks. - **Varicella Zoster Virus**: For varicella (chickenpox) in children, adolescents, and adults, and herpes zoster (shingles) in older adults, high doses of oral acyclovir are effective, especially when treatment is initiated within 24 hours of rash onset to reduce pain and accelerate healing. - **Cytomegalovirus**: Although most strains of CMV are resistant to acyclovir, it may have limited use in certain CMV infections, especially in cases where more potent drugs like ganciclovir are contraindicated.  Side Effects and Adverse Reactions  **Side Effect** **Description** ------------------------- --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Infusion Site Reactions IV therapy can cause phlebitis and inflammation at the IV insertion site. Nephrotoxicity Kidney injury can occur due to deposition of the drug into the renal tubules, which may be reversible by ensuring adequate hydration and ensuring IV formulations are infused slowly. CNS Side Effects Agitation, tremors, delirium, hallucinations, myoclonus, headache, and vertigo. GI Upset Nausea, vomiting, and diarrhea are common side effects. Precautions and Contraindications **Precautions** - Use caution in clients with renal impairment and adjust dosage accordingly.  Drug Interactions - Due to acyclovir's potential for **\[renal injury\]**, use caution with simultaneous administration of other **\[nephrotoxic drugs\]**.  Dosing, Administration, & Client Teaching **Dosing** - Dosing varies based on the condition, severity, and client response.  - Check drug dosing guidelines for individualized dosing.  - Administered topically, orally, and intravenously, with dosing guidelines varying based on the condition being treated and the client\'s renal function.  - Ensure adequate hydration during administration to prevent kidney injury.  - Reduce dosage for clients with impaired kidney function.  **Administration** - Topical, oral, or IV administration.  - Administer IV acyclovir slowly (over one hour).  **Client Teaching** - Advise clients to ensure adequate hydration and monitor for symptoms of renal injury.  - Teach clients to apply topical forms with a finger cot or glove to prevent spreading the virus to other parts of the body or to other people.   - Teach clients to maintain good hygiene practices around the infected areas to support healing and reduce the risk of spreading the infection.  - Inform clients that acyclovir does not cure herpes viruses.  - Educate clients with genital herpes about the importance of avoiding sexual contact during outbreaks and to always use condoms to reduce the risk of transmission.  Labs to Monitor **Basic Metabolic Panel (BMP)** - Monitor serum creatinine and blood urea nitrogen levels to assess for nephrotoxicity.