Procedure: Only the respiratory therapist commencing the oxygen administration knew of the patient’s random assignment to group. Patients received oxygen using two flowmeters attached to a duplex outlet. Only one flowmeter was attached to a humidification bottle so that randomization to either treatment was possible. The entire apparatus was covered by an opaque bag to blind patients and caregivers to the method of oxygen administration. Patients who received oxygen therapy for longer than three days (first period) were crossed over to the alternate treatment (second period) and were followed for a maximum of six days. You will always be able to find allergy medications shopping with a trusted foreign pharmacy.