Cagrilintide + Tirzepatide Dosage

Cagrilintide and tirzepatide both treat obesity, and they hit different receptors. Your provider is betting on a triple-mechanism idea. If semaglutide + cagrilintide (CagriSema) produced 20.4% weight loss in the REDEFINE 1 trial over 68 weeks (Garvey et al., 2025), then swapping in tirzepatide should in theory match or beat it. Tirzepatide alone reached 20.9% weight loss at the 15 mg dose in SURMOUNT-1 (Jastreboff et al., 2022).

Here is the mechanism map in plain terms. Cagrilintide is a long-acting amylin copy. Engineers attached a fatty acid chain so it sticks to your blood albumin and lasts a full week (Kruse et al., 2021). It quiets glucagon, slows your stomach, and tells your hypothalamus that you are full.

Tirzepatide is the dual-receptor drug. The GLP-1 side slows your gastric emptying and pushes insulin when you eat. The GIP side improves how your fat cells handle insulin and may soften the nausea you would get from GLP-1 alone.

No Phase 3 trial has tested cagri + tirz head-to-head. The closest data is REDEFINE 1 (cagri + sema) and SURMOUNT-1 (tirz alone). Anyone who sells you this stack is extrapolating.

Some compounding pharmacies offer both drugs and market a co-administration protocol. This is a regulatory grey zone. Tirzepatide is FDA-approved and patented by Eli Lilly. Cagrilintide had its NDA filed in December 2025 and is still unapproved. For the legal context, see FDA peptide crackdown and are peptides legal.

The most common compounded protocol stacks both injections on the same day, raises one drug per month, and holds at maintenance once you find the dose your gut tolerates.

The core rule: never escalate both drugs in the same week. Bump cagri from 0.5 to 1.0 mg AND tirz from 5 to 7.5 mg in the same week, and you have effectively doubled hunger suppression overnight. Expect 2 to 3 days of brutal nausea, possible vomiting, and a real risk of dehydration that lands people in the ER. Spacing the bumps by a month gives your body time to settle.

Slower is always safer. If a dose level gives you 5 to 7 days of nausea, hold for an extra 4 weeks before the next step. The CagriSema trial logged 79.6% GI side effects at similar levels with cagri + sema. Tirzepatide alone already runs 30 to 50% nausea, so cagri + tirz likely lands in the 60 to 80% range during titration.

Injection day looks like this: both drugs are subcutaneous, both are weekly. Use two separate syringes and two separate sites. Left abdomen for one, right thigh for the other works fine. Never mix them in the same syringe. See best injection sites for tirzepatide and the tirzepatide dosage calculator for site rotation guidance.

CagriSema is Novo Nordisk's investigational drug. It is cagrilintide and semaglutide co-formulated in one vial, one weekly injection. Your cagri + tirzepatide stack is two separate drugs, two separate shots, no FDA approval.

The GIP angle is the big "maybe" of your stack. Tirzepatide's GIP receptor activation is one reason it beat semaglutide in head-to-head data (22.5% vs 14.9% mean weight loss). If that GIP effect adds to cagrilintide's amylin effect, your stack could in theory beat CagriSema. That is speculation until a real trial runs.

The flip side is also real. Side effects from GLP-1, GIP, and amylin all converge on similar gut pathways. Nausea does not stack neatly. A 30% nausea rate from tirz plus a 40% rate from cagri is not 70%. The combined rate often pushes past 80% at peak titration, which is when most people quit. CagriSema's co-formulation at lower effective doses may be friendlier to your stomach than your two-shot stack.

For the cagrilintide monotherapy and CagriSema data, see cagrilintide weight loss dosage. For tirzepatide alone, see how to inject tirzepatide and tirzepatide dosage chart in units. For the survodutide alternative that uses a triple-receptor design natively, see survodutide vs tirzepatide.

The cumulative gut burden is the main reason to think twice about this stack. You should know what to expect on injection day and the days after.

What you can expect (extrapolated from CagriSema + tirzepatide data): - Nausea: 40 to 60% during titration weeks, dropping to 10 to 20% once you settle at maintenance - Diarrhea: 20 to 30% at peak dose levels - Constipation: 15 to 25%, often alternating with diarrhea - Vomiting: 10 to 20% during dose increases - Injection site reactions: 5 to 10% per site - Pancreatitis: rare, same risk as either drug alone, not clearly worse together - Thyroid C-cell tumor risk: tirzepatide's boxed warning still applies

Stop the stack and call your provider for any of these: - Severe abdominal pain that does not let up (rule out pancreatitis) - Vomiting that lasts more than 48 hours - Signs of dehydration: dark urine, dizziness on standing, headache - A new lump in your neck or trouble swallowing (thyroid pathology) - New mood changes or suicidal thoughts (both drugs carry this warning)

If you cannot tolerate the next titration step, drop one level, hold for 4 more weeks, and try again. Do not skip a maintenance dose of either drug. Miss your cagrilintide for more than 10 days and you essentially restart the titration clock for that drug. Tirzepatide has a 5-day half-life and is more forgiving.

Drug interactions: both drugs slow your stomach, which can wreck the absorption of any oral medication you take within 2 hours of injection. This matters most for oral contraceptives, thyroid meds, and warfarin. See tirzepatide drug interactions for the full list that applies here.

For the broader safety picture on GLP-1 stacking, see can tirzepatide cause anxiety and tirzepatide long-term side effects.

You are a reasonable candidate if: - You have plateaued on tirzepatide alone at 15 mg for 6+ months and still have significant weight to lose - You are working with a specialist who knows this is unapproved - You are willing to titrate slower than either drug alone would require

You are a poor candidate if: - You are starting your first GLP-1 (start with tirzepatide or semaglutide alone first) - Your BMI is under 30 with no metabolic issues (the risk does not justify a triple-agent stack) - You have a history of pancreatitis, medullary thyroid carcinoma, or MEN-2 syndrome (both drugs are contraindicated) - You are pregnant, breastfeeding, or planning conception within 2 months (both drugs are contraindicated) - You found this stack on social media and called it "next level". Marketing is not evidence

What this stack will not do for you: - Speed up weight loss past what tirzepatide alone produces (unproven) - Reduce side effects compared to either drug alone (it adds them) - Replace protein, resistance training, and sleep - Work without consistent weekly dosing

If your real problem is plateau, fix the protocol you have first. The usual culprits: protein under 1.6 g/kg lean mass, no resistance training, fewer than 7 hours of sleep, and hidden calorie sources you stopped tracking. See why am I not losing weight on tirzepatide for the full plateau checklist before you add a second drug.