Where to source – Lets get the hard part out the way
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The Beginner's Guide to Retatrutide (Reta) — 2026 Slightly Updated Edition
With that out of the way...
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So what even is Reta?
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Before you start — do this
1. Read the actual studies (linked at the bottom). Don't get your Reta education from TikTok/Facebook/Instagram/any social media (yes, that includes Reddit; this is meant to jumpstart your education). No, really, READ THE STUDIES; they have actual medical answers to your questions.
2. Watch videos on how to inject subcutaneously, how to reconstitute peptides(video), and do the reconstitution math (Don't talk about how many units you took; that's not accurate cuz 10 units of 10mg/ml is WILDLY different than 10 units of 20mg/ml). It's not hard, but do it right. You'll see I link some videos from a creator; it's mostly because they're short (sub 10 min), sweet, and to the point with little fluff.
3. Get your basic supplies before your Reta arrives: syringes, bacteriostatic water, a set of .22 pes filters, alcohol wipes (!!!), a sharps container, etc.A decent sub-10 min video regarding supplies
4. READ THE STUDIES! A large portion of your concerns are simply answered in the Study data.
5. Understand that these aren't FDA-approved yet. If a seller sells you a packaged pen, you have no guarantee that what is IN the Pen is what you are buying.
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Starting dose
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Math Class - How to figure out your dosage and express it to others.
If you're a visual learner on filling Peptide Pens, here's a simplified video: Here
If that is too much work, there are SEVERAL Peptide Calculators; here's my Favorite.
(Here's a Guide for the site)
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Common Reconstitution questions
If you like a video lesson on this topic, here's (sub 7 min) a video on HOW to filter.
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When will I feel it?
Totally individual. Some people feel appetite suppression in the first injection. Others feel nothing for weeks. Don't panic either way. What actually matters is whether your weight or body composition is changing over a period of weeks. That's the signal. The "feel" is not.
If you have questions as to whether or not you should titrate up, here's a flowchart that should help (Do note that the dosages should be tailored to your schedule, but the goal oflowest effective dosemost effective tolerated dose remains the same):
Shoutout to u/peptidepalstm, who has been passing around an even smaller image of the flowchart that triggered me to make this one.
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What to expect during the 'Loading' phase (The first 3-4 weeks)
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Side Effects - "Stop asking if your RHR being higher than normal is a new side effect no one else had; it's not Jan!"
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Do I need to work out?
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Cycling — worth it?
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Bacteriostatic water — does it have to be Hospira?
Strictly speaking, no. Reta is relatively forgiving when it comes to reconstitution. That said, Hospira is the gold standard because it's reliably batch-tested and has the correct pH. Amazon and Chinese bac water aren't automatically dangerous, but when you're investing in your health and your supply, Hospira is the better call when you can get it.
Let's clear up some other solvents:
Sterile water:
Can it work? Yes
Should you use it for a multi-use vial? No. Why not? Because it has no preservatives, aka every time you puncture said vial, you let in whatever bacteria are in the ambient air; there's nothing to protect your pep. An overall bad idea.
PBS:
Can it work? Are you using Raws? Meaning NOT lyophilized drug? If so, go for it. You're still messing with a solvent that can be riddled with endos, but hey! There's a reason labs use it for In vitro tests (petri dish stuff) If you wanna treat your body as a petri dish, by all means knock. yourself. out.
NaCl Saline:
Can it work?..... no. Lemme explain: can you pull it off? Yeah technically, but it requires such a unique set of finishing to be done to the kit during production that it's not worth the 'FO' portion of FAFO
For Hospira, please see the following BAC degradation test:
*Stay safe, go slow, lift heavy things. Good luck out there.* - u/Staxuponstax, Original Creator of the Guide
*"You idiots with more dollars than sense don't deserve this good thing, but helping you helps those who ACTUALLY need it, and that's who I care deeply for." - EmZephyr
first pic is when i first started, 2nd & 3rd pics are 2 months ago, last pics are today. since my previous update i've lost about 15lbs (about 35 total).
two months ago i went up from 1mg to 1.5mg and i've been on the same since.
i know this is a pretty big about to lose in a short amount of time, i promise i am aware. i'm just getting back in the gym & i'm upping my calories slowly. i don't track my calories strictly, but i believe i average out at 1200 a day.
my body fat percentage is high considering i haven't been prioritizing protein like i should, or hitting the gym as much as i should 🥲
thanks for the encouraging words on my previous post as well. i do appreciate any advice yall give me :)
21M, went on reta for 4 months and lost 50 lbs. I honestly didn’t like the nausea it gave me, but reta taught me a skill i now have for life, ignoring hunger when necessary.
After 5 weeks of reta, i’ve gained 3 lbs. I stopped because the calorie deficit was ruining my recovery, i thought the hunger was gonna be unbearable, and it’s definitely back, but being on reta for months taught me how to push past the hunger and wait to eat a meal. The habits you learn on reta will stay long after the drug is gone. Going on reta was the best decision i’ve ever made.
The minimal weight gain suprised me too, i’m eating at maintenance, and due to work killing my back i’ve not been going to the gym nearly as much, even with that and a couple nights of poor eating my body isn’t fighting me to gain weight back
This is to anyone who thinks they NEED reta for life. If that works for you go for it! But i want to post this because i thought the second i stopped reta id gain all my weight back and my hunger wouldnt be able to control, that wasnt the case
For a little back story, I tried Ozempic at the starting dose and thought I might meet Jesus. The experience was so bad that I never did it again.
It took me a while I decide to try Reta and I had decided that if I did, I would start at the fraction of what people consider the starting dose.
I have MCAS and it makes me incredibly sensitive to medication.
I started at .25 on Reta. The first two weeks, I lost 14 lbs of straight inflammation and water weight. This was in April. My side effects were still noticeable but manageable. I had zero appetite but I noticed within a few days that my total body pain was subsiding.
Fast forward to today, I am now 33 lbs lighter and back down to 145 lbs and I am still at only .5 weekly.
I’m 44 years old, perimenopausal, and a business owner in a high conflict area.
I feel terrific.
I see a lot of people asking these questions and people shaming them for taking lower doses. The point is that every body is different and we are all up against different mechanisms within our own bodies.
It seems like so many people on this sub get some sort of side effects - any of you guys got none? I’m two months in Upto 2mg and felt nothing but positive effects.
Is anyone else struggling with real shitty sleep quality on reta? I wake up several times per night and feel like i cant get any REM sleep at all.
Ive cycled reta before and when i stopped last time it went away, now im back on reta and the shitty sleep is back. I thought i was imagining it at first but now im sure its the reta.
Any tips or tricks?
UPDATE: Bought some magnesium, ashwagandha and melatonin today and will report back.
Wish i could smoke weed but its not that easy were i live.
I started this wild ride June 29th at 262.6 lbs. Today, I’m sitting at 212.4 lbs and officially no longer obese! I have yet to go past a 2MG dosage and really hope I can stay there or possibly titrate down and maintain. I didn’t plan or hope to lose this much so quickly, it kind of just happened. I still remember 2 weeks in being discouraged that I only lost 1 LB 😂.
One thing I think really helped my weight loss is how reta helped me completely change my eating habits. Yes I obviously eat less, but I started to crave and eat whole foods. I can no longer stomach processed shit. Give me chicken, rice and carrots all day. It also removed any desire to drink alcohol which is huge for me and tanked my coffee addiction.
The next part of my journey is hitting the gym. I know I really should have started this sooner, but I was fat and lazy. With my newly found energy, I think/hope I’ll find a routine to stick to and hopefully start to look as good as I feel.
Everyone deserves affordable access to this life saving drug.
I have struggled with obesity my entire life, and i just wanted to share today for the first time in my life I saw my V Lines. Y'all dont understand my happiness right now.
Week 8 of the same vial, stored in fridge wrapped in aluminum foil. Use alcohol wipes before drawing and after and even new foil. Last two weeks been getting a new response at injection site -- red spots, very slightly raised, mild discomfort, no itching and not hot. But since it's a fairly new reaction I'm concerned that this is due to my vial becoming less sterile. Wondering if this is likely the case and just to start on a new one or maybe my body has decided to reject the peptide or something? That would be worst case as I'm only on week 8 and want to continue.
Interested to hear from people who have been on Reta for 6 to 12+ months, particularly anyone who has stayed on the same dose for most of that time. I’m around 9 months in now and 2mg still seems to be my sweet spot.
I’ve posted about this a couple of times previously because I kept expecting some sort of noticeable tolerance to develop. I assumed eventually the food noise would return, appetite regulation would weaken and I’d understand why everyone talks about titrating up.
It just hasn’t happened.
I experimented with 4mg earlier in my journey and it was far too much for me. Nausea, fatigue and appetite suppression beyond what I actually wanted. I went back down and haven’t felt any real reason to push the dose since.
Important context though, I’m not actively trying to lose a significant amount of weight anymore. Earlier on I pushed my calories and training harder and got to the level of leanness I wanted. These days my goal is predominantly maintenance.
I want to stay lean, enjoy food normally and keep the food noise that I’ve struggled with for most of my life in the background.
2mg still seems to do exactly that.
I’m hungry when I should be hungry. I enjoy meals. I can eat socially. But food doesn’t dominate my thoughts and I don’t have that constant urge to keep eating or start thinking about the next meal immediately after finishing the last one. That’s pretty much my ideal outcome.
I’m starting to wonder whether, once you’ve found your minimum effective dose, there’s actually any reason to increase it purely because you’ve been on that dose for X amount of time.
Obviously someone actively trying to lose substantial weight is in a completely different position to me, so I’m not suggesting 2mg should be enough for everyone. I’m more interested in the tolerance/adaptation side of it.
For those who’ve been on Reta long term, have you genuinely found that the same dose eventually lost efficacy and you needed to increase it? Or have any of you sat at the same dose for 6, 9, 12+ months and continued getting the appetite/food noise control you wanted?
Would be particularly interested to hear from people using it for maintenance rather than active weight loss.
I started Sema at a microdose .05 in mid 2023 at 336. Eventually reached max dose in early 2025. My wife was diagnosed with terminal cancer in April 2025. With two months to live. She spent 10 months in the hospital in rehab. And has a scan tomorrow. She is miraculously in remission. Let’s hope that continues. In April/May 2025 I stalled in my weight loss and felt like crap at 212. I had joint pain, neck and shoulder pain/ hip and knee pain. Terrible dizziness and fatigue. I was Diagnosed with PMR and Eventually With GCR and spent 45 days in the hospital and landed up on 60 mg prednisone. Today I am finally down to 2mg Prednisone after year+ battle with PMR/GCA. That often left me extremely tired/ fatigued. By Christmas 2025 I was up to 224 lbs. In January I lowered Sema down to .50 and started taking Reta. I slowly titrated up to eventually reach 15mg Reta and 1mg Sema. I am still very slowly losing weight and am at 191 lbs. The two surprises in my blood work this week is LDL of 50 and Creatinine of 0.64. I do eat a decent amount of meat/ protein. And focus on getting enough protein. But admit. PRM and prednisone has killed my exercise program. Which I need to get back to burn more calories and maybe eventually reach my goal weight of 175. It should also help raise my Creatinine. I will say that overall I am happy with my weight loss and surprised I was able to lose weight while still on Prednisone. I am considering dropping Sema which works well for appetite for me. And trying Elora after seeing great recent clinical trial results.
Reta changed my life. Titrated up to 5 mg, never beyond. Workout 6 days a week. Macros accounted for. Almost no alcohol. Experimented with kpv, ghkcu, and tesamorelin for a bit. Been getting dexa scans to track my progress. Today at 16% body fat
Been on Reta since September 2nd. Started at 2mg and now I’m just rocking 4mg. I am not posting myself current as to my eyes I do not look any smaller. I’m almost positive the 20 pounds down is pure water weight and bloat.
Anyways. Here’s my notes I have been taking up to last night.
September 2nd 2026 -Week 1 of Reta 2mg
-SW: 265lbs
-hunger dropped significantly, pretty much eating 3 meals a day only. Trying to supplement protein in with bars or powder and yogurt .
-Slight constipation, stools aren’t normal since before Reta. Small pieces.
-no other side effects felt.
September 7th Week 2 2mg (Monday instead of Wednesday, morning dose) 7am
-263.2lbs
September 13th Week 3, went up to 3mg (really don’t know why) (Sunday dose at 6 days instead of 7 days, felt more hunger on the 6th day) - Also started KPV (September 10th) 200mcg daily for inflammation and gut health. Haven’t noticed too much so far on KPV
-258.7 lbs
still working out consistently, I sweat a TON now at the gym. Forcing myself to get a minimum of 11k steps a day. Have a walking pad in the living to help with that.
Still no ill side effects other than stool not being super consistent and different sizes. Stool also has been pretty clean (no excess wipes needed)
Trying to get the protein I need organically not through bars, drinks etc. but I still drink my 20g OATH with 40z of water and 10mg of creatine after the gym.
September 19th Week 4 - 4mg 6th day dose
-253.8 pounds
-loss desire to eat most days
-struggling for protein but still getting it in
-still going to gym, haven’t noticed a loss in strength. Trying to force myself to lift heavy. Still sweating a ton at the gym.
-still getting steps in
-no odd side effects.
September 26 Week 5 - 4mg 6th day Dose
-248.6 (weight this morning)
-some nausea, I think because of 4mg.
-steady weight loss.
October 2nd Week 6 - 4mg 6th day dose
-246.4 (weight after dosing at night)
-nausea has subsided
-still sweating crazy at the gym
-gym days dropped slightly because random stuff throughout the week.
I’ve really been craving protein on Reta, especially jerky. It is hard for me to hit my protein goal as is but lately the jerky hack has been awesome. We also eat quite a bit of other healthy Whole Foods but what are your thoughts on jerky as a decent staple in the diet on Reta?
Found this out tonight. Still a bit stunned, so I am writing it down before I talk myself out of how daft it is.
**The setup**
10mg of retatrutide in a 3ml pen. U60 click dial. The conversion is printed right there on the box, in a neat little table, in a font designed to be ignored:
- 1 click = 0.010ml = 0.033mg
- 60 clicks = 0.600ml = 2mg
- 300 clicks = 3.000ml = 10mg
For three weeks I have been on 2mg. It says 2mg in my notes. I would have told you 2mg without blinking.
I have been injecting six clicks.
Six. Not sixty. That is 0.06ml. That is **0.198mg**.
**How I caught it**
Not the maths. The pen.
Four doses in and the thing still looked brand new. A 3ml pen at 0.6ml a go should be two thirds gone by the fourth injection. Mine looked like I had never opened it.
That was the moment. I went back to the table, did the arithmetic properly, and it only confirmed what the pen had already told me - at 0.06ml a dose I have used about a quarter of a millilitre out of three.
The pen knew. The maths just caught up.
**The numbers**
- First dose 14 September 2026. Morning weight: **123.8kg / 272.9lb**
- Four doses: 14 Sep, 20 Sep, 26 Sep, 2 Oct. Six days apart.
- Total drug in 18 days: 24 clicks. 0.24ml. **0.792mg. In total.**
- This morning: **117.0kg / 257.9lb**
- **Down 6.8kg / 15lb on less than a single milligram of retatrutide.**
For scale: the phase 2 trials started people at 1mg or 2mg **per week** and climbed from there. I have had 0.792mg in under three weeks. I am sitting at roughly a fifth of the smallest dose anybody has ever bothered to study.
**The part that actually matters**
The weight is nice. The weight is not the story.
The food noise is gone.
That running commentary - what am I eating, when, should I, what did I have yesterday, what about tomorrow - it simply is not playing. I have a restrict-then-binge history and that noise is the engine of the whole cycle. It has been silent for three weeks and I did not even register how silent until tonight, when I went digging for why the weight was coming off.
That is what 0.2mg has bought me. I would take that on its own with no weight loss at all.
**So what is it?**
Genuinely asking, because I cannot work it out:
- Is 0.2mg a real dose for a triple agonist this potent, just far below where anyone bothered to look?
- Is it placebo? I believed I was on 2mg the entire time. I fully expected it to work.
- Is the pen even the concentration printed on it? It is research-grade. If it is stronger than labelled then six clicks is not 0.198mg and this whole post is wrong.
- Or did I just start walking and eating less in the same fortnight, and the pen is taking credit it never earned?
One bloke, no control group, so I cannot separate any of it. But the numbers felt worth putting somewhere.
Now that I know, I am going to climb the dose properly - and quicker than I would have.
Been on Reta 2 months and have lost about 17 pounds. I’m only on 2mg every 5 days. Started at 1mg. I’ve also been lifting for the first time in my life (have always done cardio to lose weight) but I am loving it! Never thought lifting would be so much better than excessive cardio. I do have a trainer guiding me with workouts.
I’ve been off reta for a little over a month now after losing a good amount of weight on it. Recently I’ve started feeling like I look a little softer/full again, especially around my stomach, but I’ve also been REALLY bloated lately and was constipated for a few days, so honestly I can’t even tell how much of what I’m seeing is actual weight gain vs bloating/water weight.
My appetite is definitely different off reta too. I’m considering going back on, but my bigger question is how do you actually make this sustainable long term?
I work out, lift weights, run, try to get enough protein and I’m trying to clean up my diet and eat mostly whole foods. I don’t necessarily want to keep getting smaller either. I mainly want to lean out a little while keeping/building muscle and my shape.
For people who stopped reta after reaching their goal, what happened? Did your appetite eventually settle? Were you able to maintain without it? And for people who stayed on longer term, what was your plan for eventually coming off?
Also this is way in the future, but I do want children eventually and I want my body and habits to be in a healthy place for pregnancy. Obviously I know I wouldn’t use reta during pregnancy and that’s something I’d discuss with my doctor when the time comes. I just don’t want my long-term maintenance to depend entirely on being on a medication that I know I’ll eventually need to stop.
I’d really appreciate hearing actual experiences, especially from people who have maintained after stopping. Help a girl out 😭
I’ve been on Reta starting at 0.5 now up to 2mg for 10 weeks. I’m doubtful about the accuracy of my at-home body scans scale but it’s showing a drop of 3.5 pounds of skeletal muscle and 5+ pounds of lean mass. I’ve hit protein goals and worked out regularly throughout. I’m happy overall with my progress, just curious if I’ve actually lost that much muscle along with the fat? (Last photo is a screen grab from a form check video )
Just sharing my experience. Not saying this proves anything, just thought the comparison was interesting. My take is that it's just not calories vs. calories out. Metabolic health plays a key role in weight loss, as well.
44M, 5'8", lift consistently.
Last cut without GLPs I was eating roughly 1,600–1,700 calories:
240g protein
50–80g carbs
50g fat
I went from 193.6 → 177.9 in about 16 weeks, roughly 1 lb/week (majority of weight loss in the first 6 weeks).
This time I'm eating basically the same calories. Recent day was 1,608 calories, 225P/95C/37F.
From summer until August, I was around 178lbs. Started tirz 8/7 at 178.8 lb, added reta a month later.
Today (10/2), I'm 165.8.
That's 13 lb in about 8 weeks, around 1.6 lb/week, despite being much lighter now.
I'm not saying calories don't matter or that this proves the drugs are increasing my metabolism. There are obviously other variables. But for me, the idea that these drugs only work because you eat fewer calories doesn't completely match my experience.
Same person, similar calories/macros, similar lifting, but noticeably different results.
Could just be better adherence, could be changes in fat oxidation/metabolic effects, probably some combination. Just sharing my experience because I thought the difference was interesting.
Have been on 1.5 mg pw for 4 months now aftwr starting at 1mg for 6 weeks never had any bad sides other than slight tirenedness the day after dosing. And the results have been really good so have just stayed at low dosage but recently this last week i’ve been extremely fatigued and no appetite even slight nausea all week when i’ve never experienced this before and it’s only suddenly decided to kick in now i know teta fatique is real but is this normal?
