The study proposes a method for assessing pollen-related morbidity based on medication usage data derived from prescription coding. The data pertain to the general health insurance population of the Puy-de-Dôme department. Weekly monitoring of medication users was conducted from January 1, 1999, through December 31, 2001, based on the date of medication dispensing. Three groups of medications were studied: antiallergics, antibiotics, and antidiabetics. The results show a significant seasonal peak in the spring. A quantification method is proposed to estimate, at a minimum, the number of people affected by pollen-related allergic symptoms in the spring (2.2% of the population). The data suggest the presence of other peaks in medication use linked to pollen outside the May–June period. The study highlights the problem of inappropriate antibiotic prescriptions, which, if not accounted for, would likely lead to an underestimation of pollen-related morbidity. Long-term monitoring of these data should make it possible to assess whether or not there is an increase in the prevalence of pollen-related allergic reactions.