Tirzepatide: A Tracking Guide for the Dual GLP-1 / GIP Titration

Tirzepatide is a dual GLP-1 / GIP receptor agonist marketed as Mounjaro for type 2 diabetes and Zepbound for chronic weight management. In December 2024 Zepbound also became the first drug ever approved by the FDA for moderate-to-severe obstructive sleep apnea in adults with obesity, on the strength of the SURMOUNT-OSA trials - a reminder that these compounds do more than move a number on a scale. The GIP arm is what distinguishes it from semaglutide, and most of the practical differences in side-effect profile and titration experience trace back to it. This post is the single-peptide tracking guide. If you are weighing tirzepatide against semaglutide, that comparison post is separate.

What it does

Tirzepatide activates both GLP-1 and GIP incretin receptors. The combined effect: slower gastric emptying, reduced appetite, improved postprandial glycemic control, and at maintenance dose, meaningful weight loss in trials. The GIP component appears to contribute additional weight loss and, anecdotally, a different GI side-effect signature.

Typical protocol shape

The standard prescribed titration:

• 2.5 mg weekly for 4 weeks (starter, not maintenance)
• 5 mg weekly for 4 weeks
• Step up by 2.5 mg every 4 weeks as tolerated
• Maintenance commonly 5, 10, or 15 mg weekly

Each step is a re-evaluation point. The pattern is: change dose, hold 4 weeks, evaluate, step up only if side effects are manageable.

What to track daily

• Appetite (1 to 10)
• Nausea (0 to 10)
• GI symptoms: bloating, constipation, reflux, sulfur or "rotten egg" burps
• Hydration (ml or cups)
• Energy
• Mood
• Any food aversions

The sulfur burps are a hallmark of GIP activation in some users. They are not dangerous but worth logging — they often correlate with delayed gastric emptying and may be a warning sign that you stepped up too fast.

What to track weekly

• Weight (same scale, same time of day, ideally morning fasted)
• Waist circumference at the navel
• Photos: front, side, back
• Workout performance, especially strength benchmarks (catabolism risk at deep deficits)
• Resting heart rate

What to track at each titration step

• Date of the first new-dose injection
• All side effects in the first 7 days at the new step
• Whether you held the dose or stepped back
• Reason for any deviation

This is the most useful retrospective data you will have. Peptid AI stores it per-step so you can see at a glance which step was the inflection point.

Bloodwork worth doing

• Baseline: HbA1c, fasting glucose, lipid panel, CMP, CBC, TSH
• 12 weeks: HbA1c, fasting glucose, lipid panel
• 6 months: full repeat
• If you have a personal or family history of medullary thyroid cancer or MEN2, tirzepatide is contraindicated — discuss with your physician

Realistic expectations

Trial average weight loss at maintenance dose runs higher than semaglutide. Individual response varies enormously. The first 8 weeks are usually dominated by appetite suppression and side-effect management; meaningful body-composition change shows up over months. Lean mass loss is a real risk at aggressive deficits — protein intake and resistance training matter.

Common mistakes

• Stepping up too fast. The 4-week hold exists for a reason. Skipping it amplifies GI side effects without faster fat loss.
• Under-eating protein. Appetite suppression makes it easy to drift below maintenance protein, which accelerates lean-mass loss.
• Dehydration. Reduced thirst plus reduced food intake means less water in. Log it.
• Skipping resistance training. Cardio alone during a deep deficit on tirzepatide is a recipe for losing muscle alongside fat.
• Not logging sulfur burps and severe constipation. These are the most actionable side-effect signals.

A tracking template

• Pre-cycle: 2 weeks of baseline weight, food, training, labs
• Titration weeks 1 to 16: daily log, weekly weight and photos, per-step side-effect block
• Maintenance: weekly weight, monthly photos, quarterly labs
• Any dose hold or step-back: full reasoning logged

Safety notes

Tirzepatide is a prescription medication. Pancreatitis is a known rare risk; persistent severe abdominal pain warrants stopping and getting evaluated. Gallbladder issues occur. Contraindicated in personal/family history of medullary thyroid cancer or MEN2. Discuss with your physician before starting or changing dose.

Peptid AI is an educational and self-tracking tool. Nothing in this post is medical advice. Doses mentioned reflect what is commonly reported in research literature — they are not recommendations. Always consult a qualified physician before starting, changing, or stopping any protocol.