Disclosed is a device and method for treating a neurodegenerative disease or condition associated with neuroinflammation induced by a leukotriene. The device is a film unit dosage form having a film layer and a safe and effective amount of a leukotriene receptor antagonist or leukotriene synthesis inhibitor. The device is configured and formulated to achieve transmucosal and/or enteral delivery of the leukotriene receptor antagonist or leukotriene synthesis inhibitor. The method includes transmucosally and/or enterally delivering to an animal in need of treatment, a safe and effective amount of a leukotriene blocker capable of crossing the blood-brain barrier.