What is the ideal window to begin Nirmatrelvir with Ritonavir (Paxlovid) treatment?

Ideally within the first five days after symptoms first appear

The efficacy of antiviral medications like Nirmatrelvir with Ritonavir, commonly known as Paxlovid, is highly dependent on the timing of initiation. These drugs function by interrupting the virus's ability to multiply within the host cells. Because the viral load increases rapidly in the initial stages of infection, the treatment window is narrow. Starting the medication as soon as possible, specifically within the first five days following symptom onset, ensures that the intervention targets the active replication phase effectively. This early action is crucial for preventing the illness from progressing into more severe forms that might require hospitalization or lead to worse outcomes, as demonstrated by studies showing quicker viral clearance in patients treated early.