Phase 2 Study IV QUZYTTIR™ (Cetirizine Hydrochloride Injection) vs V Diphenhydramine

Inclusion Criteria: * Male or female patients who require treatment premedication with an antihistamine for hypersensitivity infusion reactions associated with an anti-CD20, such as Rituxan® (Rituximab) or Paclitaxel, in their first-cycle or re-treatment after 6 months or in patients with persistent infusion reactions while on maintenance or re-treatment. * 18 years of age or older Exclusion Criteria: * Receipt of an investigational drug or device within the past 30 days. * Patients with likelihood of developing or history of tumor lysis syndrome.(TLS): patients with auto-lyse, Burkitt lymphoma and diffuse large B-cell lymphoma (DLBCL) with bulky disease (single node 7 or more cm or 3 or more nodal sites with size 3 or more cm) * Patients in whom an antihistamine may be contraindicated (e.g., narrow angle glaucoma, symptomatic prostatic hypertrophy). * Patients who, in the opinion of the investigator, may not tolerate an IV injection of diphenhydramine 50 mg or cetirizine HCl 10 mg. * Receipt of any antihistamine (H1 antagonist) within the past 2 hours regardless of the route of administration, e.g., diphenhydramine, cetirizine, loratadine, fexofenadine, levocetirizine, desloratadine. chlorpheniramine, clemastine, and doxylamine * Receipt of an H2 antagonist within the past 4 hours, e.g., ranitidine, cimetidine, famotidine, nizatidine. * Receipt of doxepin within the past 24 hours; doxepin is an antidepressant, but it also has antihistamine properties. * Receipt of epinephrine (EpiPen® or any other brand) within the past 30 days. * Has known allergy to hydroxyzine, cetirizine, or levocetirizine, or diphenhydramine. * Pregnant or breastfeeding. * Any condition that in the view of the investigator makes the patient unsuitable for enrollment in this study. * Major medical or psychiatric illness, other than diagnosed cancer at the time of presentation or in the past that in the investigator's judgement they should not be enrolled in this clinical trial. * Inability to provide informed consent. * Patients on concomitant P-glycoprotein inhibitors; including antidepressants, antipsychotics (e.g., olanzapine), and benzodiazepines (e.g., alprazolam), as they may cause an increase in sedation. * Receipt of drugs that cause sedation within the past 24 hours prior to administration of the study drug.