['hiv infection']
['raltegravir 1200 mg', 'tums', 'leader antacid']

        Inclusion Criteria:

          -  Is HIV positive

          -  Is on a stable raltegravir-containing (400 mg every 12hr) antiretroviral (ARV) regimen
             for at least 1 month prior to study entry, with no changes, including dose
             adjustments; and agrees to maintain their current ARV therapy throughout the study.

          -  Be male, or a non-pregnant and non-breast feeding female at least 18 years of age at
             the pre-trial (screening)

          -  Has a Body Mass Index (BMI) =< 32 kg/m^2

        Exclusion Criteria:

          -  Has a history of clinically significant endocrine, gastrointestinal, cardiovascular,
             hematological, hepatic, immunological, renal, respiratory, genitourinary or major
             neurological (including stroke and chronic seizures) abnormalities or diseases
             (excluding HIV)

          -  Has a history of gastric bypass surgery

          -  Has a history of cancer (malignancy)

          -  Has a history of chronic diarrhea within approximately 3 months prior to the pre-trial
             visit

          -  Has a history of significant multiple and/or severe allergies (e.g. food, drug, latex
             allergy), or has had an anaphylactic reaction or significant intolerability to
             prescription or non-prescription drugs or food

          -  Has had major surgery, donated or lost 1 unit of blood (approximately 500 mL) within 4
             weeks prior to the pre-trial visit

          -  Has participated in another investigational trial within 4 weeks prior to the
             pre-trial visit

          -  Is currently taking rifampin or atazanavir or is unable to refrain from the use of 1)
             any proton pump inhibitor from two weeks prior to the study through the completion of
             Period 4, and 2) any H2-blockers, over-the-counter antacids, calcium supplements or
             multivitamins from one week prior to the study through the completion of Period 4

          -  Consumes greater than 3 glasses of alcoholic beverages or distilled spirits per day

          -  Consumes greater than 6 servings of coffee, tea, cola, energy-drinks, or other
             caffeinated beverages per day

          -  Is currently a regular user (including "recreational use") of any illicit drugs or has
             a history of drug (including alcohol) abuse within approximately 6 months of screening
      