Pharmacokinetic scatter Background: Drugs are listed with distinct pharmacokinetic parameters. These parameters provide a sense of precision for a drug and exactly how it behaves. Instructions: Read the short passage below and review the figures in the linked article (http://aac.asm.org/content/50/7/2281.full) in Antimicrobial Agents and Chemotherapy and answer the questions that follow. Learning Goal: To appreciate the broad variability in the action of drugs across different patients. One of the drugs used to prevent and treat malaria is mefloquine. Mefloquine is administered orally in its racemic form and is well absorbed. The drug is mostly excreted through the bile, meaning it is absorbed, collected in the gall bladder, excreted in bile, and exits the body in feces. Compounds found in the feces are often not absorbed, but in this case, the drug is indeed absorbed from the gastrointestinal tract.
In a study on mefloquine dosing, 50 patients received 8 mg mefloquine per kg of body mass (8 mg/kg) on Day 0, Day 1, and Day 2 of the study. Patients were then monitored for approximately one month for their Cp levels of mefloquine. From this data, the pharmacokinetic parameters of mefloquine could be determined. The ideal Cp‐time curve (http://aac.asm.org/content/50/7/2281/F2.expansion.html) shows a smooth, predictable relationship between Cp and time. The scatter plot (http://aac.asm.org/content/50/7/2281/F1.expansion.html) of the experimental data gives a much less convincing relationship based on a visual inspection. The scatter seen in the experimental graph is representative of experimental pharmacokinetic data. The behavior of a drug can vary wildly among different patients. It is for this reason, in part, that drug must have a wide therapeutic window. Please complete the online exercise. OPTIONAL‐Please participate in the online discussion forum.