Twenty-two healthy, non-smoking, non-obese, male and female volunteers between the ages of 18 and 45 years of age will be randomly assigned in a crossover fashion to receive each of two Quinine Sulfate dosing regimens in sequence with a 7 day washout period between dosing periods. On the morning of Day 1, subjects will receive either a single oral dose of Quinine Sulfate (2 x 324 mg capsules) following an overnight fast of at least 10 hours, or a single oral dose of Quinine Sulfate (2 x 324 mg capsules) 30 minutes after a standardized, high-fat breakfast. After a 7 day washout period, on the morning of Day 8, subjects will receive the alternate regimen. Blood samples will be drawn from all participants before dosing and for 48 hours post-dose to adequately define the pharmacokinetics of Quinine Sulfate. A further goal of this study is to evaluate the safety and tolerability of this regimen in healthy volunteers. Subjects will be monitored throughout the confinement portion of the study for adverse reactions to the study drug and/or procedures. Blood pressure and heart rate will be measured prior to dosing and at 1, 2, 4 and 12 hours after each dose and at study exit. A 12 lead electrocardiogram (EKG) will be recorded at study check-in and at 2, 4, 6, 12 and 24 hours after dose administration. All adverse events whether elicited by query, spontaneously reported, or observed by clinic staff will be evaluated by the Investigator and reported in the subject's case report form.