McKenna's Pharmacology for Nursing, 2e

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P A R T 2  Chemotherapeutic agents

combination with other nephrotoxic drugs, such as the aminoglycoside antibiotics. The risk of drowsiness also rises when these anti­ viral agents are taken with zidovudine, an antiretroviral agent.

KEY POINTS AGENTS FOR HIV AND AIDS The human immunodeficiency virus (HIV) attacks the helper T cells (CD4 cells) within the immune system. This virus (an RNA strand) enters the helper T cell, where it uses reverse transcriptase to copy the RNA and produce a double-stranded viral DNA. The virus uses various nucleosides found in the cell to synthesise this DNA strand. The DNA enters the host cell nucleus and slides into the chromosomal DNA to change the cell’s processes to ones that produce new viruses. This changes the cell into a virus-producing cell. As a result, the cell loses its ability to perform normal immune func- tions. The newly produced viruses mature through the action of various proteases and then are released from the cell. Upon release, they find a new cell to invade, and the process begins again. Eventually, as more and more viruses are released and invade more CD4 cells, the immune system loses an important mechanism respon- sible for propelling the immune reaction into full force when the body is invaded. ■ ■ Instruct the person about the drug to enhance knowledge about drug therapy and to promote compliance. ■ ■ Provide the following teaching: –– Avoid sexual intercourse if genital herpes is being treated because these drugs do not cure the disease. –– Wear protective gloves when applying topical agents. –– Avoid driving and hazardous tasks if dizziness or drowsiness occurs. Evaluation ■ ■ Monitor person’s response to the drug (alleviation of signs and symptoms of herpes or CMV infection). ■ ■ Monitor for adverse effects (orientation and affect, GI upset and renal function). ■ ■ Evaluate the effectiveness of the teaching plan (person can name the drug, dosage, possible adverse effects to watch for and specific measures to help avoid adverse effects). ■ ■ Monitor the effectiveness of comfort and safety measures and compliance with the regimen. KEY POINTS ■■ Drugs that interfere with viral DNA replication are used to treat herpes infections and CMV infections. ■■ Antiviral drugs are associated with GI upset and nausea, confusion, insomnia and dizziness.

Care considerations for people receiving agents for herpes virus and cytomegalovirus

Assessment: history and examination

■ ■ Assess people receiving DNA-active antiviral agents for contraindications or cautions : any history of allergy to antiviral agents to avoid hypersensitivity reactions ; renal dysfunction that might interfere with the metabolism and excretion of the drug and increase the risk of renal toxicity ; severe CNS disorders that could be aggravated ; and pregnancy or breastfeeding. ■ ■ Perform a physical assessment to establish baseline data for assessing the effectiveness of the DNA- active antiviral drug and the occurrence of any adverse effects associated with drug therapy. ■ ■ Assess orientation and reflexes to monitor CNS baseline and adverse effects of the drug. ■ ■ Examine skin (colour, temperature and lesions) to monitor adverse effects such as rashes. ■ ■ Evaluate renal function tests to determine baseline function of the kidneys and to assess adverse effects on the kidney and need to adjust the dose of the drug. Implementation with rationale
 ■ ■ Administer the drug as soon as possible after the diagnosis has been made to improve effectiveness of the antiviral activity. ■ ■ Ensure good hydration to decrease the toxic effects on the kidneys. ■ ■ Ensure that the person takes the complete course of the drug regimen to improve effectiveness and decrease the risk of the emergence of resistant viruses. ■ ■ Wear protective gloves when applying the drug topically to decrease the risk of exposure to the drug and inadvertent absorption. ■ ■ Provide safety precautions (e.g. use of side rails, appropriate lighting, orientation, assistance) if CNS effects occur to protect the person from injury. ■ ■ Warn the person that GI upset, nausea and vomiting can occur to prevent undue anxiety and increase awareness of the importance of nutrition. ■ ■ Monitor renal function tests periodically during treatment to ensure prompt detection and early intervention, should renal toxicity develop.