This is a basic guideline for all patients to follow for correct medication dosing in relation to when blood is drawn for lab testing.
 
APPLICABLE TO FASTING AND NON-FASTING

*If fasting is required, then don’t eat or drink anything besides water for at least 10 hours

Morning Draw:
Night prior:
Take all meds as normal

Morning of blood draw:
Thyroid – take no less than 2 hours prior (4+ hours is better)
Cream – apply to 1 arm 2-4 hours prior – draw from opposite arm
Troche – take normal a.m. dose 2-4 hours prior (4-6 hours is better)

Afternoon Draw:
Night prior:
Cream – apply as normal – draw from opposite arm
Troche – if dosing only in the evening, then take full dose at normal time

Morning of blood draw:
Thyroid – if a.m. and p.m., then take a.m. dose at least 4 hours prior and don’t take p.m. dose until after blood draw

– if a.m. only, then take no less than 2 hours prior (4+ hours is better)

– if p.m. only, then take the morning of – no less than 2 hours prior (4+ hours is better)

Cream – apply as normal – draw from opposite arm
Troche – if a.m. and p.m., then take a.m. dose approximately 4-6 hours prior and don’t take p.m. dose until after blood draw

– if a.m. only, then take 4-6 hours hours prior

– if p.m. only, then take morning of 4-6 hours prior

Injectable timing
Twice weekly – draw day before injection
Weekly – draw day 4 or 5
Every 10 days – draw day 5 or 6

Timing with menstrual period (if progesterone, estradiol, or FSH are being tested)
Optimal – draw 19-21 days after last period started
OK – draw 14-21 days after last period started
Acceptable – draw 10-21 days after last period started
*If cycle is irregular, then just get blood drawn when not bleeding.