An aerosol-generating system comprises a medicament source (20) and a volatile delivery enhancing compound source (10). The volatile delivery enhancing compound source (10) comprises a first sorption element (30), a second sorption element (40) downstream of the first sorption element (30) and a volatile delivery enhancing compound sorbed on the first sorption element (30) and the second sorption element (40), wherein the rate of release of the volatile delivery enhancing compound from the first sorption element (30) is greater than the rate of release of the volatile delivery enhancing compound from the second sorption element (40).