McKenna's Pharmacology for Nursing, 2e

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C H A P T E R 1 0  Antiviral agents

TABLE 10.5

DRUGS IN FOCUS Locally active antiviral agents

Drug name

Usual indications

ganciclovir (Vitrasert) imiquimod (Aldara)

Implanted for treatment of CMV in people with AIDS

Local treatment of genital and perianal warts

Contraindications and cautions Locally active antiviral drugs are not absorbed system- ically, but caution must be used in people with known allergic reactions to any topical drugs. Adverse effects Because these drugs are not absorbed systemically, the adverse effects most commonly reported are local burning, stinging and discomfort. These effects usually occur at the time of administration and reduce and dis- appear over time.

■ ■ Monitor for adverse effects (local irritation and discomfort). ■ ■ Evaluate the effectiveness of the teaching plan (person can name the drug, the dosage, proper administration technique, and adverse effects to watch for and report to a healthcare provider). ■ ■ Monitor the effectiveness of comfort and safety measures and compliance with the regimen.

KEY POINTS

KEY POINTS

■■ Some antiviral agents are available only for the local treatment of viral infections, including warts and eye infections. ■■ Topical antiviral agents should not be applied to open wounds; local reactions can occur with administration.

Care considerations for people receiving locally active antiviral agents

Assessment: history and examination

■ ■ Assess for history of allergy to antiviral agents to avoid allergic response to these drugs. ■ ■ Perform a physical assessment to establish baseline data for evaluating the effectiveness of the drug and the occurrence of any adverse effects associated with drug therapy . ■ ■ Assess the infected area, including location, size and character of lesions. ■ ■ Evaluate for signs of inflammation at the site of infection. Implementation with rationale ■ ■ Ensure proper administration of the drug to improve effectiveness and decrease risk of adverse effects. ■ ■ Stop the drug if severe local reaction occurs or if open lesions occur near the site of administration to prevent systemic absorption and adverse effects. ■ ■ Instruct the person about the drug being used to enhance knowledge about drug therapy and to promote compliance. Include as a teaching point the fact that these drugs do not cure the disease but should alleviate discomfort and prevent damage to healthy tissues. ■ ■ Encourage the person to report severe local reaction or discomfort. Evaluation ■ ■ Monitor person’s response to the drug (alleviation of signs and symptoms of viral infection).

CHAPTER SUMMARY ■■ Viruses are particles of DNA or RNA surrounded by a protein coat that survive by injecting their own DNA or RNA into a healthy cell and taking over its functioning. ■■ Because viruses are contained within human cells, it has been difficult to develop drugs that are effective antiviral agents and yet do not destroy human cells. Antiviral agents are available that are effective against only a few types of viruses. ■■ Influenza A and respiratory viruses cause the signs and symptoms of the common cold or “flu”. The drugs that are available to prevent the replication of these viruses are used for prophylaxis against these diseases during peak seasons and to treat disease when it occurs. ■■ Herpes viruses and CMV are DNA viruses that cause a multitude of problems, including cold sores, encephalitis, infections of the eye and liver, and genital herpes. ■■ Helper T cells are essential for maintaining a vigilant, effective immune system. When these cells are decreased in number or effectiveness, opportunistic infections occur. AIDS and ARC are syndromes of opportunistic infections that occur when the immune system is depressed.