Paxlovid Drug Information PDF

Overview of the Drug Class **Prototype: ritonavir and nirmatrelvir (Paxlovid)** - **Category**: Paxlovid is an oral antiviral medication composed of nirmatrelvir and ritonavir tablets, co-packaged for treating COVID-19. - **Primary Function**: This medication is used for treating...

Overview of the Drug Class **Prototype: ritonavir and nirmatrelvir (Paxlovid)** - **Category**: Paxlovid is an oral antiviral medication composed of nirmatrelvir and ritonavir tablets, co-packaged for treating COVID-19. - **Primary Function**: This medication is used for treating mild-to-moderate COVID-19 in patients 12 years of age and older weighing at least 40 kg who are at high risk for progression to severe COVID-19, including hospitalization or death. - **Unique Features**: Ritonavir boosts nirmatrelvir levels by inhibiting its metabolism. Mechanism of Action - Paxlovid, two tablets (nirmatrelvir and ritonavir) co-packaged for treating COVID-19, works by preventing the SARS-CoV-2 virus from replicating within the body. Nirmatrelvir blocks the activity of the SARS-CoV-2-3CL protease, a key enzyme the virus needs to multiply. Ritonavir slows the breakdown of nirmatrelvir, increasing its effectiveness. Indications and Therapeutic Uses - **Mild-to-Moderate COVID-19**: Paxlovid is indicated for treating mild-to-moderate COVID-19 in clients 12 years and older weighing at least 40 kg at high risk for developing severe disease. Side Effects and Adverse Reactions **Side Effect** **Description** ------------------ ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Altered Taste A frequent side effect of Paxlovid is a change in taste perception, commonly reported as a metallic or bitter taste. GI Upset Gastrointestinal upset, including diarrhea, is observed in some clients taking Paxlovid. Hypersensitivity Paxlovid can trigger hypersensitivity responses, ranging from mild skin reactions to severe conditions such as anaphylaxis, necessitating immediate discontinuation of the medication and appropriate medical intervention. Liver Injury Elevations in liver enzymes have been reported in clients taking Paxlovid. Precautions and Contraindications **Precautions** - Use with caution in clients with renal or hepatic impairment. **Contraindications** - Contraindicated in clients with a history of significant hypersensitivity to any of its components. - Contraindicated in clients with severe renal or hepatic impairment. **Black Box Warning** - This medication has many significant drug interactions due to the inclusion of ritonavir, a potent CYP3A inhibitor. This can cause toxicity of other medications in a client's drug regimen. Drug Interactions - Paxlovid can cause significant interactions with drugs metabolized by CYP3A due to its inhibition of that enzyme, potentially leading to** \[toxicity and severe or life-threatening reactions\]**. This includes many medications, including (but not limited to): - Antiarrhythmic medications like **\[amiodarone, flecainide, dronedarone, propafenone, and quinidine\]**. - Antipsychotics like **\[lurasidone and pimozide\]**. - HMG-CoA reductase inhibitors like **\[lovastatin and simvastatin\]**. - PDE5 inhibitors like **\[sildenafil\]** used for pulmonary arterial hypertension. - Sedatives like **\[triazolam or midazolam\]**. - Antianginals like **\[ranolazine\]**. - Medications for gout like **\[colchicine\]**. - Paxlovid can cause interactions with drugs that are inducers of CYP3A, causing** \[reductions in Paxlovid plasma concentrations, reduced efficacy, and potentially drug resistance\]**. This means that Paxlovid cannot be started until after these inducers are discontinued: - Anticonvulsants like **\[carbamazepine, phenobarbital, primidone, and phenytoin\]**.  - TB drugs like **\[rifampin and rifapentine\]**. - Herbal products like **\[St. John's Wort\]**. - Cancer treatment drugs like **\[apalutamide\]**. Dosing, Administration, & Client Teaching **Dosing** - Dosing varies based on the condition, severity, and client response. - Check drug dosing guidelines for individualized dosing. - Paxlovid should be initiated as soon as possible after a COVID-19 diagnosis and within five days of symptom onset. The standard dosage is 300 mg nirmatrelvir with 100 mg ritonavir twice daily for five days. - For clients with moderate renal impairment, the dose should be adjusted to 150 mg nirmatrelvir with 100 mg ritonavir twice daily for five days. **Administration** - Oral administration. There are two different drugs in the package. **Client Teaching** - Instruct clients to complete the full treatment course. - Instruct clients to isolate according to current public health guidelines in their area. - Educate clients to monitor for adverse effects and report them when appropriate. Labs to Monitor **Basic Metabolic Panel (BMP)** - Monitor renal function to determine if adjustments in dosing are required based on renal function are specified. **Liver Function Tests (LFTs)** - Monitor hepatic function due to the potential for hepatotoxicity.