Pharmacokinetics and pharmacodynamics in HAART and antibiotic therapy.

Therapeutic agents used to inhibit the HIV replication are used in combination. The achievement of effective plasma concentrations of the drug in its active form, and sustaining such concentrations for the duration of a dosing interval without exceeding thresholds of toxicity is fundamental in HIV therapy. The issues determining the absorption, biotransformation, distribution to and activity at the intended site, and elimination, are myriad and complex. Studies at molecular, cell, and tissue levels are useful for predicting the possible fate of these agents in vivo, but the wide inter individual variability shown in whole-body pharmacokinetic studies is illustrative of the difficulty in making general statements rather than more guarded recommendations.