The factors predicting an unfavourable response of genital warts to treatment have not been determined. The disease characteristics were recorded for 390 patients with genital warts and treated by cryotherapy. The time to achieve clearance was recorded. A personal and family history of asthma, hay fever or eczema, as well as a personal history of common warts and number of recurrences was obtained by telephone four to five years after the clinical visits. In multiple regression analysis, the number of lesions (P < 0.001), extent of the disease (P = 0.003) and personal history of atopy (P = 0.001) were found to influence the time until response to treatment. Similar results were obtained for family history of atopy. The number of sexual partners (P = 0.007), extent of the disease (P = 0.009) and personal history of atopy (P < 0.001) were the main factors influencing the probability of recurrence in multiple logistic regression. The results for family history of atopy were again similar. The study concludes that atopy is a major factor influencing the time frame of the therapeutic response and the probability of recurrence in patients with genital warts.