SAN DIEGO, CALIFORNIA. Iatrogenic (doctor-caused) illness is a very serious problem in the United States and many other countries. A recent study concluded that over two million hospital patients suffer serious adverse drug effects (ADEs) every year in the US alone and more than 100,000 die from these effects. It is estimated that 75 per cent of ADEs are caused by excessive doses of drugs. Dr. Jay Cohen, MD of the University of California has just completed a fascinating study that compares dosages recommended in the pharmaceutical industry sponsored Physicians' Desk Reference (PDR) with the dosages that have actually been found effective in independent scientific studies. Generally the dosages recommended in the PDR are twice as high as the independently determined dosages. Unfortunately, most (82-90 per cent) American physicians use the PDR as their sole guide to prescribing and few are aware of the independent findings. Dr. Cohen gives the following examples of the effective doses of popular medicines as determined by independent research (PDR recommendations are given in brackets):

• Amitriptyline HCL (Elavil) – 10-25 mg/day (50-75 mg/day)
• Atenolol (Tenormin) – 25 mg/day (50 mg/day)
• Cimetidine HCL (Tagamet) – 400 mg/day (800 mg/day)
• Estrogen, conjugated (Premarin) – 0.3 mg/day (.625 mg/day)
• Fluoxetine HCL (Prozac) – 2.5-10 mg/day (20 mg/day)
• Lovastatin (Mevacor) – 10 mg/day (20 mg/day)
• Propranolol HCL (Inderal) – 40 mg/day (80 mg/day)

Dr. Cohen firmly believes that many, if not most, adverse drug reactions could be avoided if physicians were aware of the fact that the dosages recommended in their prescription "bible", the PDR, are almost invariably twice as high as needed for effective therapeutic effects.
Cohen, Jay S. Dose discrepancies between the Physicians' Desk Reference and the medical literature, and their possible role in the high incidence of dose- related adverse drug events. Archives of Internal Medicine, Vol. 161, April 9, 2001, pp. 957-64 [124 references]