Brief Summary: This phase II/III trial investigates the difference in rates of infusion hypersensitivity reaction in patients with breast cancer who are receiving paclitaxel alone or in combination with other cancer drugs which require parenteral rescue medication after stopping standard pre-medications (dexamethasone, diphenhydramine, famotidine/cimetidine/ranitidine), compared to continuing premedications. Paclitaxel is a drug used to treat breast cancer, ovarian cancer, and autoimmune deficiency syndrome (AIDS)-related Kaposi sarcoma. It blocks cell growth by stopping cell division and may kill cancer cells. It is a type of antimitotic agent. However, there are side-effects and toxicities associated with repeat exposure to this pre-medication regimen. With prolonged use of paclitaxel, especially during weekly regimens, patients are exposed to repeat doses of drugs that prevent hypersensitivity reactions. Side effects include, but are not limited to, insomnia, gastritis, fluid retention, weight gain, mood changes and immune suppression. The information gained from this study may positively influence clinical practice and help researchers develop methods to safely stop pre-medications.

Detailed Description: PRIMARY OBJECTIVE: I. To estimate the difference in rates of infusion hypersensitivity reaction (HSR) requiring parenteral rescue medications following the discontinuation of pre-medications after 2 doses of paclitaxel, compared to continuing premedications, in breast cancer patients who have not experienced an infusion HSR with their first 2 paclitaxel doses. OUTLINE: Patients receive paclitaxel per standard of care as a single agent or in combination with dexamethasone intravenously (IV) and/or orally (PO), diphenhydramine IV and/or PO and either famotidine IV and/or PO, ranitidine IV and/or PO or cimetidine IV and/or PO. Patients who don't experience any infusion hypersensitivity reaction after the first 2 doses of paclitaxel are randomized to 1 of 2 arms. ARM I (STANDARD OF CARE): Patients continue on pre-medications (dexamethasone, diphenhydramine, famotidine/ranitidine/cimetidine) with all future doses of paclitaxel. ARM II (EXPERIMENTAL): Patients discontinue premedications (dexamethasone, diphenhydramine, famotidine/ranitidine/cimetidine) with all future doses of paclitaxel, unless patient develops a subsequent infusion HSR.