The second problem is the consequences that result of missing a dose since this could entail that for some time - in the 24 hours following the failure - the drug concentrations could decrease enough to stop inhibiting viral replication; this could also promote the emergence of viral strains resistant to the drugs. In principle, the implications of missing a dose depend substantially on the pharmacokinetic properties included in the QD regimen (Cmin, half-life, intracellular concentrations, and the IC50 of the HIV of each patient), so that, the higher the drug half-life and the higher the Cmin/IC50 ratio, the higher the probability that alter missing a dose the Cmin persists above the IC50 of the HIV strain of the patient. Therefore, it is important to select drugs with pharmacokinetic profiles and an antiviral potency enough for QD administration (vide infra).