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Is Fasting And Reduced Fluid Intake Required Before Urine And Blood Test?
Question: Hello
I have a drug test/HIV,STD screening test tomorrow I am required to do as a condition of my employment. The test would involve a urine sample, blood being drawn, basic measurements (Including blood pressure I imagine), what not.
Should I fast? Also would it be okay if I drank water before that? If so , how long should I fast before that?
Also I am aware that I should not obviously do drugs nor drink alcohol prior to that.
By the time, I don't do drugs as I have not actively smoked at all within the past days nor weeks. Nor have I had any sexual intercourse/contact with another person nor blood exchange to help with the information above.
I have a drug test/HIV,STD screening test tomorrow I am required to do as a condition of my employment. The test would involve a urine sample, blood being drawn, basic measurements (Including blood pressure I imagine), what not.
Should I fast? Also would it be okay if I drank water before that? If so , how long should I fast before that?
Also I am aware that I should not obviously do drugs nor drink alcohol prior to that.
By the time, I don't do drugs as I have not actively smoked at all within the past days nor weeks. Nor have I had any sexual intercourse/contact with another person nor blood exchange to help with the information above.
Brief Answer:
8-12 hours, water is ok, other fluids not.
Detailed Answer:
Hello and thank you for using HCM,
I read carefully your query.
Yes, you need to be fasting for at least 12 hours if they will draw blood for the lipids and 8 hours if they will measure sugar in the blood too.
What I tell my patients is to at around 8 pm, a light dinner, no dessert, and then in the morning its ok to drink water, but no smoking. Coffee without sugar added is also ok.
Unless you are doing very specific testing, this should be all.
I suppose though that if they would have done any test that needs any preparation in advance, they would have told you.
Hope this is helpful.
Let me know if you have further questions. Otherwise, please kindly close and rate the question.
Take care,
Dr. Papaqako
8-12 hours, water is ok, other fluids not.
Detailed Answer:
Hello and thank you for using HCM,
I read carefully your query.
Yes, you need to be fasting for at least 12 hours if they will draw blood for the lipids and 8 hours if they will measure sugar in the blood too.
What I tell my patients is to at around 8 pm, a light dinner, no dessert, and then in the morning its ok to drink water, but no smoking. Coffee without sugar added is also ok.
Unless you are doing very specific testing, this should be all.
I suppose though that if they would have done any test that needs any preparation in advance, they would have told you.
Hope this is helpful.
Let me know if you have further questions. Otherwise, please kindly close and rate the question.
Take care,
Dr. Papaqako
Above answer was peer-reviewed by :
Dr. Raju A.T
Thank you for your advice. I was thinking of drinking water in the morning. However wouldn't i be diluting the urine results ? Even tho at most im possibly planning to drink a cup or up to a bottle of water in morning.
Brief Answer:
No, drinking water wont dilute the urine results
Detailed Answer:
Hello,
No, drinking water wont dilute the urine results, not the ones that matter. There are the ketons in the urine that will get better, and indicate that you are getting hydrated.
Take care.
No, drinking water wont dilute the urine results
Detailed Answer:
Hello,
No, drinking water wont dilute the urine results, not the ones that matter. There are the ketons in the urine that will get better, and indicate that you are getting hydrated.
Take care.
Above answer was peer-reviewed by :
Dr. Raju A.T
By the way, by light dinner, do you mean I should have a good light one before 8 pm?
Brief Answer:
You are correct
Detailed Answer:
Hello,
Yes, as I have mentioned to you before, it means a light dinner at 8pm, so you will draw the blood in the morning after 8am and so you will be fasting for more then 12 hours. Its not a must though. Even 8 hours fasting may be good enough and give normal results.
Feel free to let me know if you have further questions.
Take care.
You are correct
Detailed Answer:
Hello,
Yes, as I have mentioned to you before, it means a light dinner at 8pm, so you will draw the blood in the morning after 8am and so you will be fasting for more then 12 hours. Its not a must though. Even 8 hours fasting may be good enough and give normal results.
Feel free to let me know if you have further questions.
Take care.
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Above answer was peer-reviewed by :
Dr. Vaishalee Punj
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