The first attempts on the part of physicians and pharmacists to improve medications (to eliminate their side effects) goes back to the ancient Greece and the works of Hippocrates of Kos and Galen of Pergamon, and medication enhancement constituted a pivotal subject in the Islamic pharmacology, where the independent treaties compiled in this regard point to an independent scholarship tradition. Physicians and pharmacists were well aware of the fact that any medication used in the treatment process would involve its own side effects, which were to be accounted for. Of the first treaties authored on the subject is Hubaish ibn al-Hasan al-Aʻsam’s Improvement of Medicines written in 3rd century AH. Stressing the high value of the knowledge of medicines and their respective side effects, he therein emphasizes their appropriate production and use as well as removing their side effects. After a short introduction to the laxative medicines, he gives a brief discussion on their nature, effects and proper doze; he goes on to catalog different types of each medication before suggesting solutions for eliminating their side effects. The treatise became a reliable reference material for later pharmacological and pharmaceutical books, so we find it among the oft-cited sources by Zakariyya al-Razi, al-Biruni, and Ibn al-Baytar.