Quick answer: in clinical trials, retatrutide blood pressure effects went in a helpful direction: on 12 mg, systolic pressure fell by about 9 to 14 mmHg depending on the trial.[3][5][6] At the same time, heart rate rose modestly, peaking around 24 weeks and then easing, by about 3.5 beats per minute on average versus placebo.[1][2] Low blood pressure was an occasional side effect. Retatrutide is investigational and not FDA-approved.
This page covers the numbers behind both effects, who might need extra care, and what the heart outcome trials will add. For background, see the retatrutide profile.
Blood pressure: what the trials found
Phase 2 trials
An analysis of the two phase 2 trials reported blood pressure in detail:[3]
| Trial | Dose | Systolic change vs placebo | Diastolic change vs placebo |
|---|---|---|---|
| Type 2 diabetes (36 weeks) | 12 mg | −12.2 mmHg | −2.7 mmHg (not significant) |
| Obesity (48 weeks) | 12 mg | −10.5 mmHg | −5.5 mmHg |
Source: Heerspink et al., Kidney International Reports 2025.[3]
- Reductions were dose-dependent in both trials.[3]
- In people with diabetes, the fall in systolic pressure was larger in those who started at 140 mmHg or higher.[3]
- Dulaglutide, a GLP-1 drug used as a comparison in the diabetes trial, did not lower blood pressure in that study.[3]
- Blood pressure rose back toward baseline within 4 weeks of stopping retatrutide.[3]
Phase 3 trials
Lilly has reported systolic blood pressure falls on 12 mg of:
- 9.3 mmHg in TRIUMPH-3, in adults with severe obesity and heart disease.[5]
- 14.0 mmHg in TRIUMPH-4, in adults with knee osteoarthritis (an analysis not adjusted for multiple comparisons).[6]
These are company-reported topline figures, and the full papers have not been published. The published TRIUMPH-1 and TRIUMPH-2 abstracts do not give blood pressure numbers.
High blood pressure and retatrutide
For people with high blood pressure, the trial evidence points to lower readings, not higher ones. Some people search for whether retatrutide causes high blood pressure. The trial data so far show average falls, though individual readings vary.
In the phase 2 obesity trial’s posted results, high blood pressure was listed as a side effect in a handful of people in both the retatrutide and placebo groups (for example 4 of 62 on 12 mg and 2 of 70 on placebo), with no clear pattern by dose.[13]
That does not make retatrutide a blood pressure treatment. It has not been tested for that purpose, and the effect fades when the drug is stopped.[3]
Low blood pressure: the more relevant risk
Because pressure falls, some people drop too low, especially if they already take blood pressure medicines or become dehydrated from vomiting or diarrhea.
- TRIUMPH-2: hypotension was reported in 1%, 5% and 6% of people on 4, 9 and 12 mg, versus under 1% on placebo.[4]
- Phase 2 trials: in the obesity trial, 2.4% of people on retatrutide had low blood pressure, including drops on standing up, versus 0.3% on placebo. In the diabetes trial, all four cases (1.4%) were on retatrutide.[3]
Symptoms to report include dizziness, light-headedness when standing, and fainting.
When the changes happen
In phase 3, people started at 2 mg a week and stepped up every four weeks, so the full dose was reached over several months.[5] Blood pressure was lower during treatment and rose back toward starting levels within 4 weeks of stopping.[3] Heart rate followed a different curve: it was highest around week 24 and lower afterward.[1] Ask your clinician when to check readings, particularly during dose increases or after other medicines change.
Heart rate: what the trials found
The phase 2 obesity trial found that heart rate rose in a dose-dependent way. The increase peaked at 24 weeks and declined after that.[1]
A 2026 meta-analysis that pooled heart rate data from obesity trials of this drug class estimated:[2]
| Drug | Average heart rate rise vs placebo (beats per minute) |
|---|---|
| Retatrutide | 3.46 |
| Semaglutide (injection) | 3.35 |
| Tirzepatide | 2.05 |
| Liraglutide | 2.37 |
Source: Zhang et al., European Journal of Medical Research 2026.[2]
The retatrutide figure comes from a single phase 2 trial, so it is less certain than the others. Phase 3 heart rate results have not appeared in the published abstracts or Lilly’s releases.
Why heart rate rises with this drug class is not fully understood, and the trials cannot show whether retatrutide’s glucagon activity adds to the effect.
Heart rate reports from people using unapproved products
A 2026 JAMA Network Open study of social media posts from people describing their own use of unapproved retatrutide found heart-related mentions among 7,823 users who described at least one effect: increased heart rate (4.8%), tachycardia, or a fast heartbeat (3.8%), and palpitations (1.9%).[9]
Heart events and other risk factors
- Heart events: in TRIUMPH-3, 44 people on retatrutide and 52 on placebo had a broad heart event (MACE-5). For heart attack, stroke or heart death (MACE-3), the numbers were 27 and 23. Neither difference was statistically significant.[5]
- Other markers: in phase 2, retatrutide lowered harmful cholesterol particles and, in people without diabetes, the inflammation marker hsCRP by 54.8%.[11]
- Monitoring: the phase 3 TRIUMPH trials check pulse and electrocardiograms (ECGs) throughout.[7]
- The definitive test: TRIUMPH-Outcomes is following about 10,000 adults with heart disease or chronic kidney disease to see whether retatrutide changes heart and kidney events. Its estimated primary completion is February 2029.[8]
For how approved drugs in this class performed in heart outcome trials, see GLP-1 heart outcomes.
Blood pressure medicines and retatrutide
Lilly has completed a study of retatrutide with metoprolol, a common beta-blocker, in healthy volunteers, measuring metoprolol levels in the blood. Results had not been posted as of October 2026.[10] There is no approved label yet to guide combinations.
Who should be careful
- people taking several blood pressure medicines
- people prone to dizziness, fainting or dehydration
- people with heart rhythm problems or a fast resting heart rate
- anyone using an unregulated product, whose dose and contents are unknown
Questions to ask a clinician
- Should I check my blood pressure and pulse at home, and how often?
- Would my blood pressure medicines need adjusting if I lose a lot of weight?
- Is my resting heart rate a concern with this type of drug?
See retatrutide side effects and is retatrutide safe? for the wider safety picture, and retatrutide vs tirzepatide for how the two compare.
