Build the preparation for your appointment
Search your order's tests across the 1,175 determinations in our catalog and we'll build your preparation as you add them.
Heads up: the per-test preparation instructions are stored in Spanish in our laboratory system. If you need them translated, message us on WhatsApp and we'll send them to you in English.
Search the tests on your order one by one and we'll add them here. Once they're all in, we'll show the exact preparation to follow. Note: instructions per test are shown in Spanish.
Quick guide
How to prepare for your test in 5 steps
If your specific test has a special instruction, we show it at the top when you search for it.
Check whether your test requires fasting
Most blood tests require 8 hours of fasting. The lipid panel (cholesterol and triglycerides) requires 12 hours. HIV, pregnancy tests, swabs and many others don't require fasting. Search for your test by name or code on this page to confirm the exact instruction.
General guidelines
Apply to most tests. Check the section for your specific test for exact instructions.
Water: always yes
Drink water in normal amounts during fasting. Staying hydrated makes the blood draw easier.
Mate, coffee, tea: no
They break the fast even without sugar. Same goes for juices, sodas and infusions.
No smoking 2 h before
Nicotine alters glucose, lipids and enzymes. Avoid it on the day of the test.
No intense exercise
Skip heavy training 24 h before. It can raise muscle enzymes and hormones.
Medication: check first
Generally you don't stop taking it. Typical exception: levothyroxine — take it after the blood draw.
Arrive 10 min early
Gives you time for check-in, insurance validation and starting on time.
What to bring on the day
So your appointment goes smoothly and you don't have to come back.
ID document
Physical or digital
Original prescription
Signed and stamped by the doctor
Insurance card
Physical card or mobile app
Prior authorization
If your coverage requires one — if you're not sure, we'll help you get it
The questions we get most about preparation
How many hours of fasting do I need for a blood test?
It depends on the test. Most blood tests require 8 hours of fasting. The lipid panel (cholesterol and triglycerides) requires 12 hours. Tests like HIV, pregnancy or swabs don't require fasting. Search for your test on this page to confirm the exact instruction.
Can I drink water during fasting?
Yes, water is fine in normal amounts. Mate, coffee, tea, juices, sodas and infusions break the fast even without sugar.
Do I have to stop my medication before the test?
In general no medication is suspended, unless explicitly indicated by your doctor. A common exception is thyroid medication (such as levothyroxine): postpone the dose until after the blood draw to avoid altering the values.
What do I need to bring on the day of the test?
ID document, original prescription with signature and stamp from the professional, your insurance card and the prior authorization if your coverage requires one. If you're paying out of pocket, your ID is enough.
How do I collect a 24-hour urine sample?
Start by discarding the first urine of the morning. From that point on, collect ALL urine over 24 hours in the container we give you, including the first urine of the next day. Keep it refrigerated.
What if I don't know what preparation my test needs?
Search by name or code on this page. If you can't find it, message us on WhatsApp and we'll confirm the exact instruction before your appointment.
Still have questions?
Reach us on WhatsApp and we'll confirm the exact instructions for your specific test.