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Doctor insights on: How Long Do I Fast For A Fasting Blood Test

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Can you fast too long before a fasting blood test?

Can you fast too long before a fasting blood test?

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

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I did fasting blood test at PCP for vit D and was low, took vit D &endo 12wks later took non fast test &it was normal. Should I redo a nonfast?

I did fasting blood test at PCP for vit D and was low, took vit D &endo 12wks later took non fast test &it was normal. Should I redo a nonfast?

No: You should keep supplementing with vitamin D, unless you want to get it through your diet or through sunshine. This is a common and serious deficiency and I'm glad it was detected. ...Read more

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How is low glucose (31.9 fasting*12hours* blood test) treated? Is it a life long condition? Can it be cured? Best treatments to discuss with doctor?

How is low glucose (31.9 fasting*12hours* blood test) treated? Is it a life long condition? Can it be cured? Best treatments to discuss with doctor?

Differential Dx: Treat Low Glucose with Glucose! The duration depends on the cause; there are many! A glucose of 32 in a 23 year old is definitely not normal! First needs a thorough history and physical exam with a physician in a face to face visit.
More here...

http://emedicine. Medscape. Com/article/122122-differential ...Read more

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Can not fasting before a blood test show results of acute kidney failure & I'm scheduled for another test that I will fast for amen?

Can not fasting before a blood test show results of acute kidney failure & I'm scheduled for another test that I will fast for amen?

No: Your kidney failure may be something as simple as the transient effect of a painkiller such as ibuprofen, or something as troublesome as interstitial nephritis due to the medicine you are taking for your mood. Or there may be a lab error. Hoping you get a good outcome. ...Read more

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Even if I fast I suffer from bad flatulence. Fasting was for blood test. I thought gas was related to eating. I suspected malabsorption. Any ideas?

Even if I fast I suffer from bad flatulence. Fasting was for blood test. I thought gas was related to eating. I suspected malabsorption. Any ideas?

Gas=multiple factors: The gas you pass includes air you swallow when eating plus the gas generated by gut bacteria that live off undigested material. If you don't absorb some food material, it increases the buffet that feeds the gas producing germs. But they still produce gas from material we just didn't fully absorb. Many times it is the type of gut bacteria, not your diet, that makes you gassy. Probiotics may help ...Read more

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Non fasting blood test: ALP 123, Potassium 5.2 and glucose 109. Is this normal non fast? Taking aspirin daily and nitrofurantoin 2-3 times a week.

Non fasting blood test: ALP 123, Potassium 5.2 and glucose 109. Is this normal non fast? Taking aspirin daily and nitrofurantoin 2-3 times a week.

Normal: The numbers are essentially within normal limits. Upper normal for potassium is 5.1, but due to handling errors, slight elevations are often / usually not a problem, they are an artifact. You may want to repeat the test to recheck the potassium level. ...Read more

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I am a frequent smoker (every couple days), how long will it take to show up negative on a blood test? I have a fast met. I work out regularly, 175 6'1

I am a frequent smoker (every couple days), how long will it take to show up negative on a blood test? I have a fast met. I work out regularly, 175 6'1

Beating a test: Not one of the physicians here are interested in helping you beat a drug test. All of us would choose to support you in any attempt to never pick up another cigarette in your life. But please do not ask us to break our ethics by helping you choose disease over health. ...Read more

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How long do docs recommend I should I fast before a blood test?

You might not need t: To fast. Usually this is for certain things like your glucose level. For many tests fasting is unecessary. So ask your doctor or health professional before you have your blood drawn. ...Read more

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How long do you have to fast for a blood test checking for things that acutane effects like triglycerides and cholesterol?

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 more

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What do the results of a fasting blood test indicate?

Depends on test: Ask you doctor what they are specifically testing because there are different tests that are done fasting. Most common are fasting blood sugar and cholesterol. ...Read more

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Do I need to have a fasting blood test while taking metherexate?

No: The test done to look for Methotrexate toxicity do not have to be done in a fasting state. ...Read more

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Can you have a cup of tea before a fasting blood test?

You shouldn't: While the tea by itself is considered a "liquid" only, you may mix it with sweetner or cream. Further, there can be stimulating effects, which may have a change in your glucose or Insulin release. Just better to have water only. ...Read more

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Could a fasting blood test tell if I have hypothryoidism?

Could a fasting blood test tell if I have hypothryoidism?

Possible: If the lab order included the thyroid function test. Usually the routine blood work does not include thyroid function test, unless the ordering doctor is suspecting that you have signs or symptoms of hypothyroidism. Hope this helps. ...Read more

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Can what you eat the day before affect a fasting blood test?

To a modest degree: The most important thing to to make sure you fast, not change your normal diet because of the testing. ...Read more

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Will a fasting blood test tell if I have hypothyroidism?

Will a fasting blood test tell if I have hypothyroidism?

Yes it will: To diagnose Hypothyroidism you do not have to fast, but if your blood was collected while fasting for some other reason it is ok/And will tell if you have Hypothyroidism as long as you are tested for it. You need T3T4FreeT4 and TSH level done on fasting or non fasting specimen ...Read more