A randomized, double blind, placebo-controlled trial to assess the efficacy of LipZip in reducing mouth breathing on continuous positive airway pressure (CPAP) treatment.

The intervention that will be used in this trial is a LipZip oral adhesive gel to reduce mouth breathing during CPAP treatment in patients with obstructive sleep apnea. LipZip is comprised of 54.7% purified water, 12% Gantrez MZ 955, 12% Kollidon 90F, 10% ethanol, 4.5% Dimethicone 200, 2% citric acid anhydrous, 2% xantham gum, 1.5% Sepigel 305, 1% aerosil 200, traces of potassium sorbate and disodium edetate. Gantrez MZ 955 possesses thickening and adhesive properties and is registered for use in oral care. Kollidon 90 F is used as a binding agent. Dimethicone is a medium silicon oil approved for personal care products. A 2mm to 3mm thick single line of LipZip gel will be applied to two-thirds of the lower lip where it comes into contact with the upper lip. It is applied once nightly prior to going to bed. Treatment adherence is assessed by self report diary and gel return. 1. Mouth breathing is a common problem during CPAP treatment. It is known to contribute to low adherence to treatment. Patients who have problems of mouthbreathing will be recruited. 2. Participants will be randomized between the active and non-active group. They will be on using the oral gel for 2 weeks for each group that they are assigned. 3. There will be a washout period of 2 weeks. 4.Participants will crossover to the next treatment group.