Certain factors can worsen symptoms: Prolonged visual efforts (eg, reading, working on the computer, driving, watching television) Local environments that are dry, windy, dusty, or smoky Certain systemic drugs, including isotretinoin, sedatives (eg, that have anticholinergic effects), diuretics, beta-blockers, oral contraceptives, and all anticholinergics (including antihistamines and many gastrointestinal drugs) Dehydration Symptoms lessen on cool, rainy, or foggy days or in other high-humidity environments, such as in the shower.