The purpose of this research is to see if non-drug ingredients in capsules and oral solutions affect how well drugs are absorbed. This is called "bioequivalence." Medications taken by mouth, such as capsules and solutions, need to be absorbed into the body in order to do any good. Capsules and solutions contain a drug, but also contain non-drug ingredients that are called excipients or fillers. Excipients in the capsules and solutions can impact how much drug is absorbed into the body. This is called "bioINequivalence." Capsules and solutions in this research contain the drug cimetidine. This drug is being used since it has high water solubility (can dissolve in water) and low ability to be absorbed.

The investigators anticipate that common excipients do not cause bioINequivalence. 1) The hypothesize is that commonly used excipients in oral medications change the rate or extent of Class 3 drug absorption and result in bioINequivalence. 2) Alternative hypothesis is that commonly used excipients in oral medications do not change the rate or extent of Class 3 drug absorption and do not result in bioINequivalence.

Inclusion Criteria:

• Male or Female
• Age 18-55
• Healthy volunteers: Subjects in good health, as determined by screening evaluation that is not greater than 30 days before the first drug study visit
• Willing to avoid caffeine containing products 24 hours prior to and day of study visits
• Willing to stop all over the counter medications for 24 hours prior to and during study visits
• Able to provide informed consent

Exclusion Criteria:

• Presence of significant medical disease (including cardiovascular, pulmonary, hematologic, endocrine, immunologic, neurologic, gastrointestinal or psychiatric)
• Presence of hepatic, renal disease
• Pregnant women, breast feeding or trying to become pregnant
• Excessive alcohol use (i.e. current physical, behavioral, or personal manifestations related to the abuse or dependency on alcohol)
• Routine use (i.e. daily or weekly) prescription medication except birth control pills
• Routine use (i.e. daily or weekly) use of acid blockers, antacids, anti-diarrhea, stimulants, appetite suppressants, or anti nausea medication or other drugs that modulate gastrointestinal function
• Currently taking cimetidine or medication known to interact with cimetidine
• Allergic to cimetidine
• Undergoing therapy for solid tumor or blood malignancy
• Any condition in which in the opinion of the PI or medical physician would increase risk to the subject or interfere with the integrity of the study.

healthy subjects

10 hours