C4. Randomization and Blinding: Randomization is to be done by the research pharmacist at Montefiore Medical Center in blocks of six using computer generated random number tables available online. The randomization will be stratified by study site. In an order determined by the random number tables, the pharmacist will insert medication into vials and place these vials into sequentially numbered brown paper research bags. The research bags will be distributed by express courier in batches of six to the investigators at each site. The research bags will be stored at each site in a locked location accessible to the data collectors. When a subject has been identified, the contents of each research bag will be administered by a clinical nurse. Assignment will be known only by the research pharmacist. However, the assignment will accompany each research bag, sealed in a small manila envelope, in case a medical emergency mandates that the assignment be revealed.