With the usual caveat that you shouldn't use the book for self-diagnosis and treatment, Lawrence Galton has produced a good layman's sort of Merck Manual--that Bible of summaries of disease symptoms and causes found in most physician's offices. Galton offers some extras. You can check an alphabetical list of symptoms--e.g., ""Abdominal pain--in common infection, --in malignancies, --in anemias,"" etc.--which is cross-indexed with the alphabetical list of diseases. Two sections also cross-index major drugs by brand name (followed by the generic term), giving their use and principal side effects, with an alphabetical list of symptoms from drugs. Finally, one brief section discusses ""missed diagnoses""--conditions which are uncommon and hence may not occur to the examining physician. Frequently such conditions include symptoms simulating a more common complaint or psychological state. This list includes such serious conditions as narcolepsy (characterized by an uncontrollable need for sleep and attacks of muscle weakness leading to collapse) and senile dementia--often a catchall label for the elderly, but at times a treatable, specifically caused condition. Unexpectedly, this list produced some moments of levity: ""Cough from a hair in the ear,"" for example (the hair tickles the eardrum and triggers the cough reflex). Then there is the condition ""restless legs."" Top honors go to ""turtle"" headaches, however. These happen to people who sleep with the covers pulled over their heads. Really. The disease descriptions are short and reasonably accurate, and conclude with current treatments. It is wise to remember, however, that current may not always be choice. A book like this is consonant with the present trend toward greater patient education and participation. But beware the caveat above.