Enzyme Inhibitors - Integrase Inhibitor
The integrase inhibitor treats only those clients who have HIV-1 that have become resistant to other HIV medications. It is always combined with several other antiretroviral medications.
Safety Alert
Nurses should know how to interpret their client’s HIV-related laboratory values so they can report to the provider values that may indicate the current medication therapy is not effective. The primary laboratory tests used to gauge the efficacy of current medication therapy are the CD5 T-cell counts and the HIV viral load assays. A high viral load is undesired and is usually responsible for a low CD5 T-cell count due to the destruction of these cells by the virus. In contrast, a high CD5 T-cell count is desired and is usually made possible by a low viral load. Clients should be taught to understand the relationship between these two laboratory values so they, too, can monitor the progression of their disease.
Prototype and Other Medications
Raltegravir—Classification: Integrase Inhibitors
The prototype raltegravir, is the only integrase inhibitor available at this time.
Expected Pharmacologic Action
Three enzymes are necessary for HIV replication: reverse transcriptase, protease, and integrase. Integrase helps the newly made double-stranded DNA of HIV to become integrated into human DNA. The integrase inhibitor stops HIV replication by preventing this necessary step.
Adverse Drug Reactions
Raltegravir may cause gastrointestinal effects such as nausea, vomiting, and diarrhea. It may also cause central nervous system effects, such as dizziness or headache.
Interventions
When caring for a client who will be taking raltegravir, monitor for persistent or intolerable gastrointestinal symptoms such as nausea, vomiting, and diarrhea or central nervous system symptoms such as dizziness and headache.
Administration
The integrase inhibitor, raltegravir, is available for oral use only. Clients can take this medication with or without food. It must be combined with therapy that includes other HIV medications.
Client Instructions
Instruct clients who will be taking raltegravir to report to the provider persistent nausea, vomiting or diarrhea, dizziness, or headache. Advise the client to take an analgesic prescribed by the provider for headaches and to avoid hazardous activities, such as driving, until effects on the central nervous system are known.
Contraindications and Precautions
Raltegravir is contraindicated in clients who are just beginning HIV treatment for the first time and children less than 16 years old and may be contraindicated in severe hepatic disorders. Use caution when giving raltegravir to clients who have mild to moderate hepatic disorders.
Interactions
Raltegravir has several known interactions. Rifampin and tipranavir, a protease inhibitor, combined with ritonavir to treat HIV, cause a decrease in blood levels of raltegravir. Also, atazanavir, another protease inhibitor, increases blood levels of raltegravir. For an overview of the integrase inhibitor prototype, click the button to access a medication information table.