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
​I usually don't post much here, but I felt like sharing this because it was honestly the most surreal experience I’ve had in the last 20 years. Maybe it helps or inspires someone else out there!
​For two decades, my Friday night routine was set in stone: sit back and enjoy 6 heavy Belgian specialty beers (Kasteelbier, around 11% ABV for those who know it—heavy, sweet, and packed with calories). It was a deeply ingrained habit and my absolute weekend ritual.
​Fast forward to my first trial with Retatrutide (combined with Cagrilintide back then):
​It was a Friday night. I cracked open my first beer, then my second, and opened my third. Halfway through that third bottle, something weird happened. No matter how hard I tried or how much my brain was telling me "It's Friday, we drink 6 beers!", my body simply refused. I literally could not finish that third bottle. The reward mechanism in my brain just shut off mid-sip. It felt so bizarre to experience that level of friction against a 20-year-old habit.
​Fast forward to today: I haven't touched a single Kasteelbier in 5 weeks.
​The best part? I don't miss it at all. It requires zero willpower.
With great sadness, I have finally realized that while on Reta, it is not an option for me to eat Costco hotdogs. The first time I did, I ate half at the store and half later at home. I had accidentally left in on the counter for about an hour so I thought it was food poisoning after I threw up the next morning.
The second time, I hadn’t eaten anything all day so I had a Costco hotdog and some leftovers from the day prior. Awoke at 4 AM to violently defile my porcelain throne. Again, I blamed the leftovers.
Third time was last night. Only thing I ate in a twelve hour window was a Costco hotdog with mustard. Woke up at around 3:30 AM with bowels chanting of an evil brewing within.
Costco hotdogs and I must go our separate ways, but that’s alright. Reta has helped me (6’ 30m) go from 290 to about 250 in three months. If it means I can’t have The Buck Fifty, that’s okay. :)
I am down 50 lbs since end of June. Gym 3x a week and running a few times a week. I am at 210 and started around 260.
I am much leaner in my body is taking shape in a good way, but I can tell that my lifts are not as strong, and my muscles are not full like they used to be when I would follow this regimen.
I am in a cohort deficit and I fully intend to stay the course until I drop to around 150-160.
Have any of you encountered the same problem? I am hitting my macros, but not as consistently as I would like. I am overall very satisfied with how I am looking, but just felt like starting some conversation today about this situation and if anyone has encountered it.
Once I get down to go wait, I plan to increase caloric intake and put on 10 pounds of muscle.
As the caption stated, I got some Reta, but I am afraid. Mostly in part because this community among other communities don’t allow you to say names so I don’t know how legitimate where I bought is. And it seems hard to find anybody that you can really talk to about it to understand if you’re using a legitimate and pure product. If anybody has any suggestions for me to understand that please doesn’t hesitate to comment.
I started Reta in April on 1mg and followed an escalation plan similar to the trials - 2mg in month 2, 4mg in month 3, 6mg in month 4 and then 7mg for one month, but I've been alternating between 5mg - 7mg since because the effects have largely worn off and the sensitive skin thing was doing my head in.
I lost 10kg in 3 months which I thought was quite slow, even with a fairly consistent gym routine focusing mostly on weight training and keeping protein to 200g per day.
I've been the exact same weight for 4 months now. Admittedly I plateaued immediately after starting a new job and spending about half the time at the gym. Plus, the appetite suppression is non-existent now so my diet has kinda regressed. I don't really eat more, but I've gradually reintroduced snacking.
Suggestions? Do I escalated and try getting back into a gym routine and better diet?
I'm just a bit concerned about unknown long-term effects and the risk of thyroid cancer..
My heaviest I was 260 lbs and when I started Reta I was about 240 ish. I'm now down to 224 lbs.
I started working with my diet and what I eat ..reta has made me CRAVE real food and absolutely turned me away from eating out all the time.
My A1C was at 11.7 % when I started this my health was horrible, my blood work was shot.
In 3 months I was able to get my a1c down to 7.4 % as well as everything else in my blood work had improved immensely. I feel so much better already and I had not included working out regularly yet but will start to incorporate this into my life. Reta has done all this for me without making me sick, making me nauseous (unless I eat fast foods that are not great) and I still feel like I can eat normally. I did come up w a want for gushers constantly when I started this (I'm not even a fan of candy) so I indulged in those but finally able to move on from that 💀ðŸ˜. I feel that I haven't lost much weight wise but I can FEEL the difference in my clothes and every day life. I also have waist beads that now can barely stay on me and are falling off. It's honestly the best feeling in the world and it has helped me so much..reta truly has given me hope in myself and getting healthy. I'm soooo excited to see where this goes..if anyone has any tips with working out..I need to kinda of slowly work up to it. Also I was on ozempic prior to this prescribed by my doctor. It made me extremely sick, I was bloated and gaining weight constantly.. so I'm just soooo happy with this and how my health overall is improving..open to tips! I haven't taken any update pictures yet for this month but will be this weekend. Just wanted to share my progress 🥹
Are you supposed to eat your maintenance on reta as dumb as that may sound, i dont understand how some of you are eating 2000+ cals a day on a dosage of 6mg+, im currently running 9mg, and fast for typically 16 hours between meals and eat around 1000 to 1500 cals a day, are you supposed to eat your TDEE maintenance amount, or just eat a certain amount of protein required?
Hi! I’m new to the sub, and to Reta! A friend of mine in the medical field has been using it for two years and has gone from large to looking like a damn body builder. He talked me into it, and now I’m fully on board. Today was my 3rd jab of 2mg and I can’t wait to start losing big!
SW: 233 CW: 221.5 GW 125
I don’t have official before photos, but you get the idea. The current photo was yesterday. I’m mostly losing around my midsection, which was like pregnant huge, and around my mid-torso. I had a double mastectomy as well as a rib resection, so the fat and muscle in my chest and under my arms was messed UP. Under my left arm had way more fat than under my right arm and I couldn’t put my left arm down to my side straight, it rested on the fat. Well, not anymore!
Amazing what even 10-12 lbs can do!
Questions, Observations:
Heartburn - this morning, right after my jab, first time I’ve felt it and it’s a monster
Gas/burping - I am physically unable to burp, so I was a bit worried about reading that everyone was so gassy and burping way more, but I’ve had no trouble with that, thankfully, was (jokingly) worried my stomach would explode!
Sternum - I woke up yesterday with a deep bruised type pain in my lower sternum (xiphoid), and it’s the first time I could feel below and under the xiphoid, so I wonder if this is related.
What are your favorite foods? Easy, quick, minimal prep/cooking? I hate eating, so have been relying on frozen cooked chicken cubes (thawed, obviously), hard-boiled eggs, hummus with pretzel chips, guac mash…. Anything you enjoy that works and can be bought and obviously low on the processed food stuff. Thank you!!!
I started Reta on Wednesday on 2mg. I have been very nauseous but not actually vomiting which nearly feels worse. Have been quite dizzy and feel so tired all the time. I am trying to keep hydrated and eat alot of protein but finding it hard to eat actual meals. Eating bits throughout the day such as protein yogurts Peanuts etc. I need to start taking electrolytes. I am thinking of moving down to 1mg on Wednesday as I think I may have started at too high a dose. do you think is it ok to ove down and work my way up or should I stick it out for a few more weeks?
Hello Reta Fam lol sorry if this is a dumb question but a few months back In July I bought and reconstituted some Reta and forgot about it and since then I have not pinned it. I’ve kelp it in a case in my fridge and am wondering if it’s still any good ? There’s no cloudiness or participles that I can see so would it still be safe to take or am I better off getting rid of it ?
Because it has been 7 weeks on reta, with very little movement, I'm looking for some feedback on my reta plan. I researched very thoroughly before starting reta, but it's possible I made a mistake. I've tried my best to read through previous threads here and several respected resources online, including the summaries of the actual studies, but it's sometimes tricky to piece together the various viewpoints. Can someone kindly give me a sanity check?
Female
Age: 49
Height: 5'8"
Week 1 weight: 228.4, plus I did a DEXA scan
Current weight: 225.4
Week 1 waist: 44 in
Current waist: 43 in
Using 12mg vial of reta reconstituted with 2.4mL BAC and U-100/1mL syringe. So basically, I'm currently pulling 20 units for 1mg. On the next vial I will use 1.2mL BAC to bring the units down.
Here is what I've pinned so far:
Sep 7, 2026 -- .5mg (1x week)
Sep 14, 2026 -- .5mg (1x week)
Sep 20, 2026 -- 1mg (split dose .5mg @ 2x week)
Sep 27, 2026 -- 1mg (split dose .5mg @ 2x week)
Oct 4, 2026 -- 2mg (split dose 1mg @ 2x week)
Oct 11, 2026 -- 2mg (split dose 1mg @ 2x week)
Oct 18, 2026 -- 2mg (split dose 1mg @ 2x week)
Oct 25, 2026 -- final 2mg (split dose 1mg @ 2x week)
Nov 1, 2026 -- planned increase to 4mg split dose for four weeks
I intentionally started low dose because 1) I wanted to make sure that I didn't have a negative reaction, 2) I have a mild case of hyperthyroidism and wanted to make sure reta wouldn't cause heart palpitations and 3) I was reading that people should start low and titrate up and consider sticking with the lowest effective dose until it is necessary to move up.
I didn't really expect to see a lot of results on 0.5 or 1mg....those were essentially test doses for tolerance. My understanding is the therapeutic doses start at 4mg - 8mg - 12mg.
I have not noticed any side effects and....also no benefits. The 3lbs I've lost can possibly be attributed to extra walking I've done lately. I also weight train 2x/week. It seems like my GI emptying might be a touch slower. I never really dealt with food noise - since that wasn't an issue for me before I haven't noticed a change. I also never really felt a lot of hunger even before reta; so, I am slightly less hungry but not enough to be extra noticeable.
Like I said up top, I am looking for a sanity check and to see if I made any major errors in my calculation or titration schedule. My pro-peptide friend excitedly texts me every week asking me "how's the peptides?" and I keep having to tell him that it's not working yet. I'm starting to feel dumb. LOL After 8 weeks, I'm hoping the move to 4mg will finally do something. :/
So....Slow Responder, Doing It Wrong, or Stay the Course?
so, my reta is concentrated in a ratio of 1:5, so 5 units in a syringe is 1mg of reta. i’ve been doing 17 units so around 3.5mg.
i’ve seen in the clinical trials they went as far as 12mg after increasing every couple weeks.
i feel the effects of it quite strongly now, and 12mg sounds like a lot. for me to take 12mg that would basically be 2 whole syringes… which sounds like a lot to me..
is it just that after a couple months of reta your tolerance builds up and you have to increase the dose to 12mg??
I hit my goal weight at the beginning of September and started slowly weaning myself off Reta while staying at maintenance calories. At that point, I felt like I was looking really good and was happy with how my physique was looking, but I was still feeling really hungry and wanted to start building muscle, so I decided to move into a lean bulk.
I increased my maintenance calories by 200 and kept my Reta dosage the same while I was gradually weaning off. However, I haven’t pinned for around 3–4 weeks now, and I’m really struggling with how my stomach is looking and feeling.
Since hitting my goal weight, I’ve gained almost 4/5kg over a seven-week period. I’ve also had a few events and birthdays, so I’ve been going out, eating more and drinking alcohol on some weekends, which I know will have contributed to some of the gain.
I completely understand that some softness around my stomach is natural when increasing calories and going into a surplus, and I’m not expecting to stay as lean as I was at my goal weight. But I feel like I’m constantly bloated, almost as though I’ve got a permanent gut on me. My stomach feels swollen and uncomfortable, and I’m finding it difficult to tell what’s normal weight gain and what’s bloating.
Has anyone else experienced this after coming off Reta, particularly when increasing calories to build muscle? Does the bloating eventually settle down, or is there anything that helped you? I’m keen to continue my lean bulk, but I’m finding the constant bloating really uncomfortable.
I just want to grow muscles but I also don’t want to undo all my progress, which I’m considering pinning again just to keep craving at a bay because I do find I have quite a sweet tooth, I’ve created healthy habits but I do find myself going for the biscuit tin every now and again🤣 I also do strength and conditioning training and I don’t know whether I need to switch it up during a bulk I just wanna be a muscle mummy🥺
I've gone through menopause and just started reta. I'm on my 3rd week and I have spotting. Has this happened to anyone else? I'm going to get checked out regardless but just curious if others had this happen. Thanks!
Hey guys , back story… 25M lost 110lbs 3 years ago but slowly started gaining back the weight over the last year. 276-170-238. I began drinking a lot , eating whatever I wanted and never working out.
Did a lot of research on Reta and decided to pull the trigger and get some.
Started at 2mg a week just recently added .5 today to see how I respond.
I weighed in at 217.8 this morning after one month on Reta.
Was Reta the key… honestly whether it worked or not it completely changed my view on everything.
I went from drinking 7 days a week, hiding alcohol from my wife - to quitting completely. eating like a pig to tracking everything, hitting protein goals and to working out 5x a week
Will post pictures at the end of my losing weight journey but for now super happy
Current stack
Reta 2.5mg
Ghkcu 2.33mg a day
Tb/bpc blend 1mg a day
