De Smet is a retired drug information pharmacist and clinical pharmacologist, emeritus professor of pharmaceutical patient care, and lyricist.

[30][31][32] He is currently working on a major 4P-Project (Patients Practitioners Practices Plants) that will provide global coverage of the material cultures of ethnomedicine and ethnopharmacology.

[33] He located archaeological material of the peyote cactus in the Witte Museum in San Antonio, USA.

Radiocarbon dating showed that the material was 5700 years old and chemical analysis demonstrated that the hallucinogenic alkaloid mescaline was still present.

[36] The latter project resulted in a special chapter on traditional medicine (TM) in the International Classification of Diseases (ICD 11).