Final answer:
Increased drug excretion through the urine does not increase the amount of drug in the blood; instead, it decreases drug concentrations by removing the drug from the body. Liver impairment, kidney impairment, and decreased metabolism by cytochrome P450 enzymes can all increase drug levels in the blood.
Step-by-step explanation:
The student's question pertains to factors that affect the concentration of a drug in the blood. The conditions that can increase drug concentration in the blood include liver impairment and kidney impairment, both of which can reduce the body's ability to metabolize and excrete drugs. Additionally, decreased metabolism by cytochrome P450 enzymes would lead to higher drug levels in the blood, as these enzymes play a key role in the breakdown of drugs. However, increased drug excretion through the urine should lower the concentration of the drug in the bloodstream, as it results in more of the drug being removed from the body.
Therefore, the factor that does not increase the amount of drug in the blood is increased drug excretion through the urine.