Question 1

is it necessary for me to fast before blood work?

Accepted Answer

Depends: It depends on what is being tested. Usually fasting is recommended for lipid panels & diabetes testing. Your lab or your doctor should be able to tell you prior to the test.

Question 2

hi,

my triglycerides r 234 and vldl 47. no fast before blood work. in october 2014 tri was 94 and vldl was 19. concerned. thank you. ?

Accepted Answer

Not concerned.: The primary target of cholesterol therapy is the LDL.  The TRIG and VLDL are of little consequence.  Higher TRIG was a result of not fasting.  It is good to see non fasting samples as a "worst case" scenario. Please go to the Framingham Risk Calculator and plug in your data.  You will find that your risk of heart disease in next ten years is very close to about 3%.  Not a big concern.

Question 3

how long do i need to fast for getting blood work done?

Accepted Answer

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!

Question 4

do i need to fast for preop blood work for a colonscopy?

Accepted Answer

Usually not.: Fasting is recommended when checking cholesterol and sugars.  These aren't standard blood tests associated with colonoscopies.

Question 5

can i drink black coffee before blood work that requires a 12 hour fast?

Accepted Answer

Fasting: Yes. Of course. Every primary care specialist will advise you to avoid calories when you are fasting. So water and black coffee are the two things that are allowed. Every office I have worked at tells their patients this when they are told to fast prior to coming in for these lab tests.

Question 6

i had to fast for a blood work but i drank a glass of metamucil fibre will this effect the test?

Accepted Answer

Depends: It depends on the type of Metamucil you took (regular bs sugar-free) and what you mixed it with (juice va water). And it depends on the blood test that was being collected. If you took regular Metamucil mixed in juice it will affect your blood sugar, but not your blood count, liver tests or electrolytes.

Question 7

when u fast for a routine physical blood work is the gluccose reading only show how you ate the day prior to fasting?

Accepted Answer

No: The fasting glucose is just that - your baseline fasting glucose. It has nothing to do with what you ate the day before. The point of it is to see your overall health and diet for several months. It's used to diagnose diabetes for example. Two fasting blood glucoses on separate days that are 126 mg/dl would meet one of several definitions of diabetes mellitus.

Question 8

i have to fast for 12hrs,my blood work is at 730pm,its 8am now and i took a sip of milk,will that mess up my results?can i still take my antibiotic?

Accepted Answer

No and Yes: A sip of milk or taking your prescribed antibiotic dose is unlikely to influence your labs

Question 9

should i fast for a day? my doc wants me to fast for 12 hours before i have blood work done. would it be okay to continue the fast after the lab work?

Accepted Answer

Why not: Unless you have a health condition that makes it dangerous for you to skip meals, going for one full day without food is not a problem.  Stay hydrated!

Question 10

my son who is 14 had to fast for blood work. doctor called and said his tryglycerides were high. it was 527. do i need to see a cardio doctor?

Accepted Answer

High triglycerides.: No.  A good primary care doctor can easily treat this with diet and medication.

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Doctor answers about:

Why fast before blood work

A member asked:

Is it necessary for me to fast before blood work?

A member asked:

Hi, my triglycerides r 234 and vldl 47. no fast before blood work. in october 2014 tri was 94 and vldl was 19. concerned. thank you. ?

A member asked:

How long do i need to fast for getting blood work done?

A member asked:

Do i need to fast for preop blood work for a colonscopy?

A member asked:

Can i drink black coffee before blood work that requires a 12 hour fast?

A member asked:

I had to fast for a blood work but i drank a glass of metamucil fibre will this effect the test?

A member asked:

When u fast for a routine physical blood work is the gluccose reading only show how you ate the day prior to fasting?

A member asked:

I have to fast for 12hrs,my blood work is at 730pm,its 8am now and i took a sip of milk,will that mess up my results?can i still take my antibiotic?

A member asked:

Should i fast for a day? my doc wants me to fast for 12 hours before i have blood work done. would it be okay to continue the fast after the lab work?

A member asked:

My son who is 14 had to fast for blood work. doctor called and said his tryglycerides were high. it was 527. do i need to see a cardio doctor?

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