The drug combinations needed to control HIV are difficult to take correctly, but they are only as effective as a patient's willingness or ability to take them. Increrasing attention is therefore being given to ways of increasing patient adherence. Skipping even a few doses will increase risk of treatment failure.
Protease inhibitors are some of the most difficult drugs to take correctly.
They areusually taken three times each day, but this does not mean with breakfast, with lunch and with an evening meal - it means every eight hours, irrespective of how late you stay out or how long you want to sleep. In addition, the level of PI in the bloob towards the end of each hour period can fall to levels which do not prevent the virus from growing and perhaps mutating. The level of drug in the body over the course of a day resembles three high peaks with two intervening valleys when the virus can grow. Consequently, it is important to take the proteaese pills as precisely as possible every eight hours. being late by even 120 minutes in any day can allow the virus to regain the upper hand. So taking a 'drug holiday on a Friday and Saturday evening is like playing Russian Roulette if you are taking a PI combo.