Background: Treatment of atopic dermatitis (AD) may be challenging, therefore some patients seek complementary and alternative medications (CAM). We determined prevalence and predictors for CAM use in a hospital cohort of AD patients. Material and Methods: Between January 1, 2012, and December 31, 2017, AD patients referred to the dermatological outpatient clinic at Bispebjerg Hospital were included in the study. Information on CAM use, demographics and disease characteristics were obtained by questionnaire, and associations were determined by χ2 and t test separately for children (< 16 years) and adults (≥16 years). Results: In total 441 filled in the questionnaire on AD, and 433 patients responded to the questions about CAM use: 198 children and 235 adults. A total of 137 (31.6%) had used one or more CAM. CAM use in children was significantly associated with prior use of ≥2 conventional treatments (p = 0.047) and topical calcineurin inhibitors (p = 0.021), a higher number of affected eczema sites (p < 0.001) including more frequent affection of the face and extremities, a higher SCORAD score (p = 0.045), and low mean overall self-rated health (p = 0.003). CAM use in adults was significantly associated with lower age of onset of AD (p = 0.004), comorbid allergic rhinoconjunctivitis (p = 0.039), frequent use of moisturizing cream (p = 0.024), facial and neck eczema (p = 0.005) and high educational level (p = 0.043). Conclusion: CAM use is frequent in both children and adult AD patients. CAM users are characterized by long disease duration, a significant disease burden and by having a longer education. The high prevalence of CAM may indicate that patients’ expectations regarding treatment of AD are not redeemed in the conventional health care system.