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Tirzepatide Telehealth

A plain-spoken reading desk for the dual GIP/GLP-1 record — where the beyond-glycemia trials (sleep apnea, heart failure, fatty liver, kidney) lead, explained step by step.

Tirzepatide Weight Loss: What the Studies Found

Why did Tirzepatide lead to weight-loss studies?

Tirzepatide was first made to improve blood sugar in diabetes. Early studies also showed that people ate less and lost weight. Researchers then made weight loss the main question.

SURMOUNT-1 followed adults with obesity for 72 weeks, or about 17 months. None had type 2 diabetes. At 15 mg, the average loss was 20.9%; placebo users lost 3.1%. At 100 kg, that is about 20 kg compared with 3 kg.

SURMOUNT-5 compared Tirzepatide directly with semaglutide. It included 751 adults with obesity and no diabetes. The average drop after 72 weeks was 20.2% with Tirzepatide and 13.7% with semaglutide. Each adult reached the highest dose that side effects allowed.

The medicine didn’t keep all the weight off after it stopped. In SURMOUNT-4, everyone first lost about 20.9%. By 88 weeks, the placebo group had regained most of that loss. People who stayed on Tirzepatide lost another 5.5%. For you, the result points toward care that lasts instead of a short course.

Tirzepatide weight loss: what happened in SURMOUNT-1?

The SURMOUNT-1 study followed 2,539 adults. Each had obesity, with a body mass index at or above 30. Others had a body mass index at or above 27 and a health problem made worse by weight. If you had type 2 diabetes, this study would not have included you.

This was a phase 3 study, one of the final large tests before approval. People were assigned by chance to placebo or a weekly shot. Tirzepatide doses were 5, 10, or 15 mg. Each group began at 2.5 mg and rose during a 20-week climb.

At week 72, the group averages were [4]:

  • 5 mg Tirzepatide: −15.0%
  • 10 mg Tirzepatide: −19.5%
  • 15 mg Tirzepatide: −20.9%
  • Placebo: −3.1%

Every Tirzepatide dose beat placebo by an amount unlikely to be due to chance. Nausea, vomiting, diarrhoea, and constipation were the main problems. Most began during the dose climb and stayed mild or medium [4].

A later review looked at people taking drugs that can add weight. They made up about 17–20% of the study groups. Their weight change ranged from −13.3% at 5 mg to −21.3% at 15 mg by week 72. These SURMOUNT-1 results stayed close to the main findings [20].

Tirzepatide weight loss: what happened in SURMOUNT-1?

Tirzepatide weight loss vs semaglutide: what did SURMOUNT-5 find?

SURMOUNT-5 was the first large study to compare these drugs face to face. All 751 adults had obesity, while none had type 2 diabetes. People were assigned by chance to one drug for 72 weeks.

The Tirzepatide group used 10 or 15 mg. The semaglutide group used 1.7 or 2.4 mg. Side effects set the highest dose for each adult.

At week 72, these were the average weight changes [5]:

  • Tirzepatide: −20.2%
  • Semaglutide: −13.7%
  • The average gap: −6.5 percentage points

More people taking Tirzepatide lost at least 10%, 15%, 20%, or 25%. Their waist size also fell more [5]. Both drugs helped, but Tirzepatide produced the larger average loss in this trial.

That is the plain answer to tirzepatide vs semaglutide for this group. The study can’t settle which drug fits your health, risks, or cost. That choice belongs in a talk with your prescriber.

Tirzepatide results after stopping: what did SURMOUNT-4 find?

SURMOUNT-4 asked whether weight stayed off after the drug stopped. Everyone first took Tirzepatide and lost 20.9% on average. Then 670 people either stayed on it or moved to placebo for 52 more weeks.

From week 36 to week 88, the changes were [18]:

  • Those who continued Tirzepatide lost another −5.5%, for −25.3% from the start.
  • Those moved to placebo gained +14.0%, leaving −9.9% from the start.
  • The average gap was −19.4 percentage points. The paper gave a 95% confidence range, showing how much this estimate could vary.

Blood pressure, blood fats, and sugar moved back toward their starting levels after the drug stopped. Those measures kept improving for people who stayed on it [21]. A review of GLP-1 drugs found about 9.7 kg regained after semaglutide or Tirzepatide stopped [17].

These SURMOUNT-4 Tirzepatide results show that the effect depends on continued treatment. They don’t prove every person will regain the same amount. For you, the key point is that this looks more like long-term blood-pressure care than a brief course.

Tirzepatide dosage for weight loss: what schedule did studies use?

In the SURMOUNT trials, the dosing protocol began at 2.5 mg once weekly for 4 weeks, then increased by 2.5 mg every 4 weeks as tolerated, with target maintenance doses of 5, 10, or 15 mg depending on the study arm. The once-weekly schedule is possible because of the approximately 5-day half-life that comes from the fatty-diacid albumin-binding modification [1].

The FDA-approved dosing schedule for chronic weight management follows the same stepwise titration as the trials. The full approved label and trial dosing context are covered on the dosage page.

A post hoc analysis of participants using concomitant weight-inducing medications (such as certain antidiabetic agents, antipsychotics, or corticosteroids) found that tirzepatide's weight-loss effect was preserved in this subgroup, with percentage weight reductions comparable to the primary efficacy results [20].

As this is an FDA-approved compound, the dosing information above is reported as labeled and trial-documented — not a personal recommendation. Prescribing decisions rest with a licensed clinician, and that clinician is increasingly met on a screen rather than in a waiting room: prescription tirzepatide in the US moves through licensed telehealth practices such as Promise Peptides (mypromise.com), where a prescriber evaluates the patient and sets the titration before anything is dispensed. Which of the maintenance doses above an individual ends up on is the outcome of that consultation, not a figure that can be read off a trial table.