Primary care physicians encounter a broad range of problems and therefore require a broad knowledge to manage patients. They encounter patients at early undifferentiated stage of a disease and most of the presentations are due to non sinister problems but in minority of patients same presentations could be due to serious conditions. One of the main tasks of a primary care doctor is to marginalize the risk of missing these serious illnesses. To achieve this they can look for red flags which are clinical indicators of possible serious underlying condition. Red flags are signs and symptoms found in the patient's history and clinical examination. Evaluation of red flags is of paramount important as decision making is mainly dependent on history and examination with the availability of minimal investigatory facilities at primary care level. Some Red flags like loss of weight and loss of appetite are general in nature and could be due to many pathologies while hematemesis and melena are specific red flags which indicate GIT bleeding. All red flags, whether highly diagnostic or not, general or specific, warn us the possibility of life-threatening disorders. The term 'red flag' was originally associated with back pain and now lists of red flags are available for other common presentations such as headache, red eye and dyspepsia as well. Identification of red flags warrant investigations and or referral and is an integral part of primary care and of immense value to primary care doctors.
Keywords: General practice; primary care; red flags; serious diseases.