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How Long Do You Fast For Fasting Blood Work
8 hours is common.: Most clinics will ask you to have nothing to eat after midnight, and have the blood draw first thing in the morning- so it could be 8-12 hours. You may drink non-calorie clear liquids, i.e., water, tea, coffee. Don't put milk or sugar in your beverage, or you'll have to repeat the test! ...Read more
Eight to Twelve: Eight to twelve hours should suffice.Get a more detailed answer ›
No fasting: Not requiredGet a more detailed answer ›
In a way, yes: If you fast for longer than a day or so, it will alter some blood chemistries. Fasting tests are usually set for an overnight fast, or a 12 hour fast. Prolonged fasting is starvation and it affects the body metabolism. ...Read more
About an hour: Point of care test may be available in a matter of minutes. Test done in the main lab takes about and hour. However, it usually takes longer for the results to get back to the ordering doctor due to time taken for blood collection, transportation to the lab, processing in the lab, recording of results. Retesting in a limited number of cases etc. ...Read more
How long do you have to fast for a blood test checking for things that acutane effects like triglycerides and cholesterol?
Fast for 12 hours: Accutane is used to treat acne which is severe and unresponsive to conventional therapies. While it is quite effective, Accutane has numerous side effects. It has been shown to cause transient increases in cholesterol and triglyceride levels which in turn increases one's risk of heart disease, high blood pressure, and more. It is important to check these levels regularly following a 12 hour fast. ...Read moreSee 1 more doctor answer
Most routine...: ...Fasting blood tests are not affected by recent antibiotics. For the few that are, overnight should be fine. ...Read more
Not much: If for blood sugar, you need to fast, no food after dinner,or before midnight. They will be gentle get some info and if panels will take a few vials from your arm vein or even just finger stick if just a few test. The manner depends on your docs prescription and the venue of the test: if Quest usually a couple or several small tubes are enough,not to worry less much less than donating your blood. ...Read more
Instantly: The act of drawing blood doesn't alter your blood chemistry or cell content. Even if you hyperventilate, clench your fist, or produce extra catecholamines from a serious stick, the body returns to normal within a few moments. ...Read more
3-5 days: Most labs turn over the results in 3-5 days. If you haven't heard from your doctors office within 7 days, call them. ...Read more
24-48 hours: When blood cultures are taken, they are put into a machine that looks for bacteria growing. Most hospitals have machines that constantly are looking for growth. As soon as they turn positive, the machine alerts a technician and the alert goes out to the doctor. Most physicians consider 24-48 hours a reasonable time frame. ...Read more
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