Answered by:
Stuart D. Federman, PharmD, AAHIVP
Gateway Apothecary
Saint Louis, MO


You do not want to double your dose. The way the drugs are metabolized (absorbed in the body), taking a larger dose will not make up for a missed dose.

If the medication is a once daily medication and you remember that you missed the dose within an eight to 10 hour window after your missed dose, most medications can be taken when remembered and the next dose should be taken at the regularly scheduled time. If it is past 10 hours, skip the dose that was missed and take your normal dose at the next scheduled time.

It is estimated that you need to have an adherence rate of 95 percent or higher to prevent HIV becoming resistant to the medication over time. There is nothing worse than taking medications sporadically and allowing the virus to be exposed to low levels of the drugs in the body, which will lead to resistance to the medications.

When initiating or changing regimens, ask your doctor or pharmacist what you should do if you do miss your dose since all medications are different.

Additional writing by Amanda Wong, student pharmacist at the St. Louis College of Pharmacy.