Understanding GLP-1 Dosing: mg, mL, Units & Common Additives Explained
Updated: Oct 23
If you are starting semaglutide or tirzepatide treatment, you may notice terms like:
mg
mL
units
B12
B6
L-Carnitine
At first, these labels can seem confusing. Understanding what they mean can help you feel more comfortable and confident with your treatment.
What Does “mg” Mean?
mg stands for milligrams and refers to the amount of medication itself.
Examples:
1mg semaglutide
2.5mg tirzepatide
In general, a higher mg number means a higher medication dose.
What Does “mL” Mean?
mL stands for milliliters, which measures liquid volume.
The amount of liquid in a syringe does not always equal the amount of medication. Different pharmacies may prepare medications at different concentrations.
For example:
Two patients may inject the same number of “units”
But receive different medication doses depending on concentration
This is why it is important to always follow your specific prescription instructions.
What Are “Units”?
Many compounded GLP-1 prescriptions use U-100 insulin syringes, which are marked in units rather than milliliters.
On a U-100 syringe:
50 units = 0.5 mL
25 units = 0.25 mL
10 units = 0.1 mL
These measurements describe liquid volume—not the milligram amount of medication.
The number of milligrams delivered depends on the medication's concentration (mg/mL).
Never calculate or change your injection amount based on another patient's instructions. If your pharmacy, vial concentration, or prescription changes, confirm your dosing instructions with your prescribing provider or pharmacist before injecting.
Why Do Different Pharmacies Use Different Strengths?
Compounded GLP-1 medications may come in different:
vial sizes
concentrations
total medication amounts
This does not necessarily mean one medication is “stronger” or “better.” It simply means the dosing instructions may differ depending on the pharmacy and formulation.
Always follow:
your prescription label
your physician’s instructions
your dosing schedule
Common Additives Explained
Some compounded formulations may include additional ingredients.
Why Does My Medication Look Red or Pink?
Some compounded GLP-1 medications may appear red or pink because they contain Vitamin B12 (Cyanocobalamin or Methylcobalamin).
Vitamin B12 naturally has a deep red color, which may give certain compounded formulations a red or pink appearance. However, medication appearance alone cannot confirm its identity, quality, or safety.
Some pharmacies include Vitamin B12 in compounded formulations as part of the preparation prescribed by your healthcare provider.
If you ever notice:
Cloudiness
Particles
Unusual discoloration
Changes in appearance compared with previous vials
Contact your healthcare provider or dispensing pharmacy before using the medication.
Always follow the instructions provided with your prescription.
Vitamin B12 (Cyanocobalamin or Methylcobalamin)
Vitamin B12 is an essential nutrient involved in:
Normal red blood cell formation
Nervous system function
Energy metabolism
Some compounding pharmacies include Vitamin B12 in certain GLP-1 formulations. However, adding B12 has not been established to improve the weight-loss effectiveness of semaglutide or tirzepatide.
Vitamin B6 (Pyridoxine)
Vitamin B6 is an essential vitamin involved in:
Protein and amino acid metabolism
Normal nervous system function
Red blood cell formation
Some compounded GLP-1 formulations may contain Vitamin B6. Its inclusion does not necessarily mean the medication will produce greater weight loss or fewer side effects.
L-Carnitine (Levocarnitine)
L-Carnitine is a naturally occurring compound involved in transporting fatty acids into cells, where they can be used to produce energy.
Some compounded formulations may include L-Carnitine. However, its addition has not been established to improve the weight-loss effectiveness of GLP-1 medications.
Important Safety Reminder
Never assume:
more liquid means a stronger dose
another patient’s syringe markings match yours
all pharmacies use the same concentration
If you ever have questions about your medication or dosing instructions, contact your healthcare provider before injecting.
Questions About GLP-1 Treatment?
Northern Colorado Medical provides physician-supervised semaglutide and tirzepatide treatment throughout Colorado through convenient telehealth visits.
Transparent Pricing • No Memberships • Ongoing Support
Call or Text: 970-557-1269
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