Dennis McKenna is an ethnopharmacologist, author, and brother to psychedelics proponent Terence McKenna. His new book is called "Ethnopharmacologic Search for Psychoactive Drugs: 50 Years of... Read allDennis McKenna is an ethnopharmacologist, author, and brother to psychedelics proponent Terence McKenna. His new book is called "Ethnopharmacologic Search for Psychoactive Drugs: 50 Years of Research (1967-2017)".Dennis McKenna is an ethnopharmacologist, author, and brother to psychedelics proponent Terence McKenna. His new book is called "Ethnopharmacologic Search for Psychoactive Drugs: 50 Years of Research (1967-2017)".