This medication is primarily used as an antiviral treatment for COVID-19, containing Nirmatrelvir and Ritonavir. Nirmatrelvir works by inhibiting the replication of the SARS-CoV-2 virus, thereby preventing its proliferation. Ritonavir regulates the metabolism of Nirmatrelvir, increasing its concentration in the blood and maximizing its therapeutic effect. This medication is particularly effective in reducing hospitalization and mortality rates in high-risk patients, with a more pronounced effect when treatment is initiated early. Additionally, due to potential interactions with various other medications, caution is required when co-administering this drug. To maximize the efficacy of this medication, it is essential to consider the patient's condition and existing medications, ensuring appropriate dosage adjustments and monitoring.
Index
- A. Key Information
- A.1. Ingredients
- A.2. Appropriate Users
- A.3. Side Effects
- A.4. Dosage Instructions
- B. Additional Information
- B.1. Age
- B.2. Birth Control
- B.3. Breastfeeding
- B.4. Kidney Function
- B.5. Liver Function
- B.6. With Food
- C. Drug Interactions
- C.1. Eliquis(Apixaban)
- C.2. Statins
A. Key Information
This medication is primarily used as an antiviral treatment for COVID-19, containing Nirmatrelvir and Ritonavir. Nirmatrelvir works by inhibiting the replication of the SARS-CoV-2 virus, thereby preventing its proliferation. Ritonavir regulates the metabolism of Nirmatrelvir, increasing its concentration in the blood and maximizing its therapeutic effect. This medication is particularly effective in reducing hospitalization and mortality rates in high-risk patients, with a more pronounced effect when treatment is initiated early. Additionally, due to potential interactions with various other medications, caution is required when co-administering this drug. To maximize the efficacy of this medication, it is essential to consider the patient's condition and existing medications, ensuring appropriate dosage adjustments and monitoring.
| Category | Details |
|---|---|
| Product Name | Paxlovid Tab. |
| Ingredients | Nirmatrelvir 150mg / Ritonavir 100mg |
| Form | Oral Film-coated Tablet |
| Company | Pfizer |
| ATC Code | J05AE30 (Nirmatrelvir and Ritonavir) |
| Dosage & Administration |
- Start administration within 5 days of COVID-19 symptom onset - Recommended dosage: 300mg Nirmatrelvir (2 tablets) + 100mg Ritonavir (1 tablet) - Take for a total of 5 days (30 tablets in total) |
| How to Take | - Nirmatrelvir and Ritonavir must be taken together; taking Nirmatrelvir without Ritonavir may not provide a sufficient therapeutic effect. |
| Packaging Unit | 30 tablets (1 box) |
A.1. Ingredients
• Nirmatrelvir
- Role -
Nirmatrelvir inhibits the main protease (3CL protease) of the SARS-CoV-2 virus, preventing viral replication. This inhibition suppresses the virus's proliferation, slowing the progression of the infection.
Nirmatrelvir inhibits the main protease (3CL protease) of the SARS-CoV-2 virus, preventing viral replication. This inhibition suppresses the virus's proliferation, slowing the progression of the infection.
- Characteristics -
Nirmatrelvir is an effective antiviral agent for treating COVID-19, particularly when used in the early stages of infection.
Nirmatrelvir is an effective antiviral agent for treating COVID-19, particularly when used in the early stages of infection.
• Ritonavir
- Role -
Ritonavir is primarily used as an antiviral agent in the treatment of HIV. In Paxlovid, Ritonavir inhibits the metabolism of Nirmatrelvir, increasing its concentration in the blood. This enhancement amplifies the effect of Nirmatrelvir.
Ritonavir is primarily used as an antiviral agent in the treatment of HIV. In Paxlovid, Ritonavir inhibits the metabolism of Nirmatrelvir, increasing its concentration in the blood. This enhancement amplifies the effect of Nirmatrelvir.
- Characteristics -
Ritonavir acts as a CYP3A enzyme inhibitor, necessitating caution due to potential interactions with other medications.
Ritonavir acts as a CYP3A enzyme inhibitor, necessitating caution due to potential interactions with other medications.
A.2. Appropriate Users
This medication contains Nirmatrelvir and Ritonavir and is primarily used to treat COVID-19. Administration is contraindicated in certain patient groups, such as those with severe hypersensitivity to the active ingredients of this drug, or when co-administered with strong CYP3A inducers.
A.3. Side Effects
Common side effects include neurological symptoms, vascular hypertension, gastrointestinal symptoms (abdominal pain, nausea, vomiting), and general fatigue or malaise at the administration site. Additionally, there is a risk of serious adverse reactions due to drug interactions, particularly with medications metabolized by CYP3A, requiring careful monitoring when co-administered.
A.4. Dosage Instructions
This medication can be taken with or without food and must be swallowed whole without chewing or crushing. The recommended dosage is 300 mg of Nirmatrelvir (two 150 mg tablets) and 100 mg of Ritonavir (one 100 mg tablet) taken together orally twice daily for 5 days. If a dose is missed and it is within 8 hours of the scheduled time, take it as soon as possible. If more than 8 hours have passed, skip the missed dose and continue with the next scheduled dose.
B. Additional Information
B.1. Age
• Pediatric Patients
The safety and efficacy of Paxlovid in pediatric patients have not been established. Therefore, the use of this medication in children is not recommended. Due to the lack of clinical data for pediatric patients, alternative treatment options should be considered after consulting with a healthcare provider.
• Elderly Patients
Paxlovid can be used in elderly patients, and clinical trials have included individuals aged 65 and older. Research has not shown significant differences in safety between older and younger patients. However, elderly patients may have increased sensitivity to the medication, so caution is advised. Dose adjustments or additional monitoring may be necessary for elderly patients.
B.2. Birth Control
• Types of Hormonal Contraceptives
Oral contraceptives containing hormones such as ethinyl estradiol should be discontinued for 5 days while using this medication. Additionally, it is recommended to use an alternative non-hormonal contraceptive method for one complete menstrual cycle before and after the use of this medication.
• Interactions
Hormonal contraceptives may have reduced effectiveness when used in conjunction with certain medications, potentially decreasing their contraceptive efficacy. Therefore, caution is advised when using other medications while on hormonal contraceptives to avoid reduced pregnancy prevention effectiveness.
B.3. Breastfeeding
• Presence of Nirmatrelvir in Breast Milk
Data on whether Nirmatrelvir is present in human or animal breast milk is limited. In studies with lactating rats, temporary weight loss was observed following Nirmatrelvir administration.
• Presence of Ritonavir in Breast Milk
Limited data indicate that Ritonavir is present in breast milk. However, there is no information on its impact on breastfeeding infants or milk production.
• Benefits and Risks of Breastfeeding
Breastfeeding offers benefits for infant development and health, but the clinical need for this medication and potential adverse reactions in the infant while breastfeeding should be carefully considered.
• Precautions for Breastfeeding Mothers with COVID-19
Breastfeeding mothers infected with COVID-19 should take precautions to prevent exposing their infants to the virus, following relevant guidelines and recommendations.
B.4. Kidney Function
• Dose Adjustment Based on Renal Function
Mild Renal Impairment (60 ≤ eGFR < 90 mL/min): No dose adjustment is needed.
Moderate Renal Impairment (30 ≤ eGFR < 60 mL/min): Administration at specific doses is required.
Severe Renal Impairment (eGFR < 30 mL/min): Use of this medication is not recommended.
Moderate Renal Impairment (30 ≤ eGFR < 60 mL/min): Administration at specific doses is required.
Severe Renal Impairment (eGFR < 30 mL/min): Use of this medication is not recommended.
• Precautions for Patients with Renal Impairment
In patients with reduced renal function, the drug's plasma concentration may increase, which could lead to significant adverse effects. Therefore, caution is necessary.
B.5. Liver Function
• Hepatic Impairment
1. Mild or Moderate Hepatic Impairment (Child-Pugh A or B)
No dose adjustment is required for patients with mild or moderate hepatic impairment.
No dose adjustment is required for patients with mild or moderate hepatic impairment.
2. Severe Hepatic Impairment (Child-Pugh C)
There is no pharmacokinetic or safety data available regarding the use of Nirmatrelvir or Ritonavir in patients with severe hepatic impairment. Therefore, this medication is not recommended for use in patients with severe hepatic impairment.
There is no pharmacokinetic or safety data available regarding the use of Nirmatrelvir or Ritonavir in patients with severe hepatic impairment. Therefore, this medication is not recommended for use in patients with severe hepatic impairment.
• Hepatotoxicity
Ritonavir has been associated with elevated liver transaminases, clinical hepatitis, and jaundice in patients. Caution is advised when administering this medication to patients with pre-existing liver conditions, liver enzyme abnormalities, or hepatitis.
B.6. With Food
PAXLOVID can be taken with or without food. It should be swallowed whole and should not be chewed, broken, or crushed.
C. Drug Interactions
C.1. Eliquis(Apixaban)
• Interactions
When used in combination, the plasma concentration of Apixaban may increase, leading to an elevated risk of bleeding. Therefore, caution is necessary when co-administering Apixaban with this medication.
• Recommended Dosage
The recommended dosage when co-administering with Apixaban should be adjusted based on the dosing of Apixaban. Additional information should be referenced from the prescribing guidelines for Apixaban.
C.2. Statins
• Interactions with Lovastatin and Simvastatin
- Due to the potential risk of muscle disorders, including rhabdomyolysis, co-administration with Lovastatin and Simvastatin is contraindicated.
- If the use of this medication is medically necessary, Lovastatin and Simvastatin should be discontinued 12 hours prior to starting this medication, during the 5-day period of use, and for 5 days after completing this medication.
- If the use of this medication is medically necessary, Lovastatin and Simvastatin should be discontinued 12 hours prior to starting this medication, during the 5-day period of use, and for 5 days after completing this medication.
• Interactions with Atorvastatin and Rosuvastatin
- Consider temporarily discontinuing Atorvastatin and Rosuvastatin while administering this medication.
- There is no need to temporarily discontinue Atorvastatin and Rosuvastatin before or after the administration of this medication.
- There is no need to temporarily discontinue Atorvastatin and Rosuvastatin before or after the administration of this medication.
