Andrew for many years taught clinical pharmacology and therapeutics at various London Medical Schools.  From 1963 until 1992 he also edited Drug and Therapeutics Bulletin, published by Consumers' Association.  He was Extraordinary Professor of Clinical Pharmacology at the University of Groningen from 1968-77, and for some years co-edited Side Effects of Drugs.  He has also long been a consultant to the World Health Organization. 

After 3 years as part-time consultant at the UK Cochrane Centre he became its Emeritus Fellow.  He is a co-convenor of the Cochrane Adverse Effects Methods Group, helping authors to improve the reporting of harms in systematic reviews (www.aemg.cochrane.org). In 1996 he co-founded the DIPEx project which runs two large databases of personal experiences of health and illness - www.healthtalkonline.org, www.youthhealthtalk.org