Flapping tremor is an important clinical sign indicative of metabolic encephalopathy. It is also known as ‘asterixis’. Common causes of flapping tremors are: - Chronic kidney failure - Severe congestive heart failure - Decompensated liver disease - Respiratory failure Reference: https://www.google.com/search?q=what+causes+flapping+tremor&oq=what+causes+flap&aqs=chrome.1.69i57j0l2j0i10j0l3j0i22i30j0i10i22i30j0i22i30.4402j0j9&sourceid=chrome&ie=UTF-8