How to Dose Semaglutide and Tirzepatide: Full Protocol Guide
Titration schedules, BAC water reconstitution, syringe unit conversion, injection technique, and missed dose rules -- everything in one place. The syringe math is where most people get it wrong, and the calculator handles all of it.
TL;DR -- Start low, titrate slowly, pick one day per week and stick to it. Converting mg to syringe units requires knowing your BAC water volume -- use the calculator to avoid errors.
Essential Tools
Calculate Your Exact Dose
The syringe unit math depends entirely on how much BAC water you used. The calculator takes your vial size, water volume, and target dose and gives you the exact number of units to draw on any insulin syringe.
The standard protocol mirrors the clinical Ozempic/Wegovy schedule. Each step lasts a minimum of 4 weeks. If side effects are significant, stay at the current dose for 8 weeks before stepping up.
Phase
Dose
Duration
Notes
Start
0.25 mg
Weeks 1-4
Introductory dose. Not therapeutic -- builds tolerance.
Step 2
0.5 mg
Weeks 5-8
First effective dose. Many people see appetite suppression here.
Step 3
1.0 mg
Weeks 9-12
Strong appetite suppression. Most common maintenance dose.
Step 4
1.7 mg
Weeks 13-16
Optional intermediate step before maximum.
Max
2.0 mg
Week 17+
Ceiling dose. Most people do not need this to reach goal.
Find your sweet spot. Most people land between 0.5mg and 1.7mg as their maintenance dose. You do not need to reach 2.0mg. Once weight loss is sustained for 4 weeks at a given dose, that is likely your dose.
Tirzepatide Protocol
Tirzepatide Titration Schedule
Tirzepatide is a dual GIP/GLP-1 agonist with a longer titration ladder. The steps are larger and the full schedule runs 20+ weeks to reach maximum dose. Most people find their maintenance dose well before the ceiling.
Phase
Dose
Duration
Notes
Start
2.5 mg
Weeks 1-4
Introductory dose. Builds tolerance before first step-up.
Step 2
5.0 mg
Weeks 5-8
First active dose. GIP + GLP-1 effects both engage.
Step 3
7.5 mg
Weeks 9-12
Significant appetite suppression. Many people maintain here.
Step 4
10.0 mg
Weeks 13-16
Strong response. Common plateau before step-up decision.
Step 5
12.5 mg
Weeks 17-20
High dose. Only move here if 10mg is well-tolerated and results stalled.
Max
15.0 mg
Week 21+
Ceiling dose. Most people do not need this.
No need to chase the maximum. Clinical trial data shows diminishing returns above 10--12.5mg for most people. If you are losing weight steadily at 7.5mg, stay there.
Mixing
How to Reconstitute with BAC Water
GLP-1 peptides come as lyophilized (freeze-dried) powder. You add bacteriostatic water (BAC water) to create an injectable solution. The volume of water you add determines the concentration -- and therefore your syringe draw for every dose.
Standard semaglutide mix (10mg vial). Add 2mL of BAC water. This gives a concentration of 5mg/mL. A 0.25mg dose = 0.05mL = 5 units on a U-100 syringe.
Standard tirzepatide mix (10mg vial). Add 2mL of BAC water for 5mg/mL concentration. A 2.5mg dose = 0.5mL = 50 units on a U-100 syringe.
Inject BAC water slowly down the vial wall. Never inject directly onto the powder -- this damages the peptide. Angle the needle so the stream runs down the glass. Do not shake. Swirl gently until dissolved.
Store reconstituted vials in the fridge. 2-8 degrees C. Keep away from light. Shelf life is typically 28-56 days after reconstitution depending on the peptide. Check your source's guidance.
This is where almost everyone gets it wrong the first time. An insulin syringe measures in "units" (U), not milliliters. On a U-100 syringe, 100 units = 1mL. The conversion math ties your mg dose to your BAC water volume.
The formula:
Units to draw = (Dose in mg / Vial mg) x (Water added in mL) x 100
Example: 10mg vial, 2mL BAC water, 0.5mg dose
(0.5 / 10) x 2 x 100 = 10 units
If you change the amount of BAC water you add, every dose changes too. A 10mg vial with 1mL of water is twice as concentrated as one with 2mL. The calculator accounts for all of this automatically -- just update the inputs whenever you open a new vial.
Never guess. Eyeballing syringe draws on GLP-1s causes either underdosing (no effect) or overdosing (severe nausea, vomiting). Take 30 seconds with the calculator before every new vial.
GLP-1s are subcutaneous injections -- into the fat layer just beneath the skin, not into muscle. Correct technique prevents bruising, lumps, and absorption problems.
1
Choose your site. Abdomen (at least 2 inches from the navel), outer thigh, or upper outer arm. Rotate sites with each injection to prevent tissue buildup (lipohypertrophy).
2
Clean the site. Wipe with an alcohol swab and let it air dry for 10 seconds. Injecting wet skin stings and increases contamination risk.
3
Pinch the skin. Use your non-dominant hand to gently pinch a fold of skin. This lifts the fat layer away from muscle, ensuring a true subcutaneous injection.
4
Angle and insert. Insert at 45 degrees for lean sites or thin individuals. 90 degrees is fine on the abdomen if you have adequate fat tissue. Use a 29-31 gauge, 4-8mm needle.
5
Inject slowly. Push the plunger steadily over 5-10 seconds. Rapid injection increases sting and blowback. Hold for 5 seconds after the plunger bottoms out before withdrawing.
6
Do not rub the site. Light pressure with a clean cotton ball is fine. Rubbing disperses the peptide too fast and increases bruising.
Site rotation matters. Injecting the same spot repeatedly builds scar tissue that absorbs peptides inconsistently. Map out a rotation: left abdomen, right abdomen, left thigh, right thigh -- and cycle through.
Scheduling
Pick a Day and Stick to It
GLP-1s are weekly injections. Consistency matters -- the 7-day interval is built into the titration schedule and the half-life of the drug. Irregular spacing can cause gaps in coverage and unpredictable side effects.
Pick one day. Friday or Saturday evening works well for most people -- side effects (nausea, fatigue) peak 6-12 hours post-injection and are often milder if you can rest through them.
Set a calendar reminder. Same day, same time. GLP-1s have a long half-life (semaglutide ~7 days, tirzepatide ~5 days) but a consistent schedule prevents accidental double-dosing or long gaps.
Travel and time zones. You can shift your injection day by up to 2 days in either direction to accommodate travel without restarting titration. Just resume the original schedule after.
Missed Dose
What to Do If You Miss a Dose
Missing a weekly injection happens. The rule is simple and the same for semaglutide and tirzepatide.
Within 5 days of the missed dose: Take it as soon as you remember. Then resume your normal weekly schedule from that new injection day.
More than 5 days since the missed dose: Skip it entirely. Do not try to make it up. Inject on your next regularly scheduled day as if nothing happened.
Never double-dose. Taking two doses back-to-back dramatically increases nausea, vomiting, and cardiovascular stress. There is no benefit and significant risk.
After a long gap (2+ weeks): Some providers recommend dropping back one titration step when restarting after an extended break, since tolerance to side effects fades. Check with your provider before resuming at your previous dose.
Managing Side Effects
Use Slower Titration to Reduce Nausea
The titration schedule is not a hard rule -- it is a minimum. If you are struggling with nausea or other GI side effects, the single most effective intervention is slowing down.
1
Stay at the current dose longer. Instead of moving up every 4 weeks, extend to 6 or 8 weeks. Your GI tract adapts -- give it time. There is no clinical benefit to rushing.
2
Use a half-step. If the jump from 0.5mg to 1.0mg semaglutide feels too big, try 0.75mg for 4 weeks. The calculator handles any custom dose. Same principle applies to tirzepatide steps.
3
Inject at night. Peak nausea typically hits 6-12 hours post-injection. Evening injections let you sleep through the worst of it.
4
Small, low-fat meals the day after injection. GLP-1s slow gastric emptying. Large or fatty meals the day after injecting cause the most severe nausea. Eat small, bland, easily digested foods for the first 24 hours post-injection.
Slower is smarter. People who rush titration often quit due to side effects. People who titrate slowly tend to stay on protocol and see better long-term results.
Long-Term Dosing
Finding Your Maintenance Dose
The goal is not the maximum dose -- it is the lowest dose where you are losing weight steadily (or maintaining goal weight) without intolerable side effects. This is your maintenance dose.
Signs you have found your dose. Consistent appetite suppression, steady weight loss of 0.5-1.5 lbs per week, side effects mild or absent after 4 weeks at the current dose.
Dose creep is not always needed. If semaglutide 1.0mg is working well, there is no reason to move to 1.7mg. Higher doses increase side effect risk and cost without proportional benefit for many people.
Plateau at low dose? If weight loss has stalled for 4+ weeks at a given dose, stepping up may be appropriate. But rule out caloric compensation and poor sleep first -- these are more common plateau causes than insufficient dose.
Weight regain on discontinuation is expected. GLP-1s suppress appetite pharmacologically. When discontinued, appetite returns. Most people need ongoing low-dose maintenance or a transition plan.
FAQ
Common Dosing Questions
How do you convert semaglutide mg to insulin syringe units?
It depends on how much BAC water you used. If you reconstituted 10mg in 2mL of BAC water, you have 5mg/mL. A 0.25mg dose = 0.05mL = 5 units on a U-100 syringe. The ASCEND calculator does this math automatically -- enter your vial size, water volume, and target dose.
What is the standard semaglutide titration schedule?
0.25mg weekly for 4 weeks, then 0.5mg for 4 weeks, then 1.0mg for 4 weeks, then optionally 1.7mg, then 2.0mg as the ceiling. Most people find their maintenance dose between 0.5mg and 1.7mg. You do not need to reach 2.0mg.
What is the tirzepatide dosing protocol?
Tirzepatide starts at 2.5mg weekly and steps up by 2.5mg every 4 weeks: 2.5, 5, 7.5, 10, 12.5, and 15mg. Most people find their effective maintenance dose between 7.5mg and 12.5mg. The 15mg maximum is rarely necessary.
What do I do if I miss a GLP-1 dose?
Within 5 days of the missed injection, take it and resume your normal schedule from that new date. More than 5 days: skip it entirely and inject on your next scheduled day. Never double-dose under any circumstances.
How much BAC water should I use for reconstitution?
The most common approach for a 10mg vial is 2mL of BAC water, yielding 5mg/mL. For a 5mg vial, 1mL gives the same concentration. Any water volume works as long as you enter it into the calculator -- the units-to-draw calculation changes based on concentration.
Not medical advice. This guide is for educational and research purposes only. GLP-1 receptor agonists are prescription medications. Consult a licensed healthcare provider before starting, adjusting, or stopping any protocol.
