Jumping from Tirz to Reta - starting dose?

Wallydog

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I've been using tirz 15mg/week for about 6 months but it seems to be less effective at quelling the food noise so I am considering a switch to Reta based on popular opinion here. Do I need to start at the "baby dose" of Reta to start off since I'm already hitting the GLP-1 and GIP receptors with tirz? Just interested in hearing opinions on what dose to start with and what levels people find to be effective. Thanks.
 
I made it up to 12.5 mg / week on Tirz and it just stopped Tirzing. The sides were murder, so I made the change to Reta. I started at 2 mg, and titrated up another 2 mg / week until I hit 8 mg. I dose 4 mg every 84 hours now. Once my next kit arrives I'll up to 5 mg every 84 hours, for a month or so, and then consider 6.

I have better hunger suppression on Reta then I did on Tirz, but I don't know if that's the general experience of people on Reta.

If the Reta ever stops Reta-ing, I'll probably add Cagri.
 
I made it up to 12.5 mg / week on Tirz and it just stopped Tirzing. The sides were murder, so I made the change to Reta. I started at 2 mg, and titrated up another 2 mg / week until I hit 8 mg. I dose 4 mg every 84 hours now. Once my next kit arrives I'll up to 5 mg every 84 hours, for a month or so, and then consider 6.

I have better hunger suppression on Reta then I did on Tirz, but I don't know if that's the general experience of people on Reta.

If the Reta ever stops Reta-ing, I'll probably add Cagri.
Most people say tirz is better at supression.
 
Most people say tirz is better at supression.
That's my general sense from here too. I find that Reta, I guess, mentally? makes me not want to eat, whereas the Tirz physically prevented me from eating due to gastric transit times, etc. But I still had the same pull to food that I always did. That pull is absent on Reta.
 
I made the switch from Tirz to Reta when I was taking 2.5mg 2x weekly. I was worried about sides, so I took numerous (~12) small doses (1-2.5mg) in 15 days to work my level up quickly, but not overshoot my level and end up having to ride it hell. My reading suggested GCGR signaling (what I was wanting) would be reliably engaged around 6-8mg/week steady state.

During the bridge I took two more doses (2.5mg and 2mg) of Tirz to control food noise on day 4 and 11 of the bridge.

Saturday will make 6 weeks since I started the bridge. 19 doses administered totaling 53-54mg. I'm working on dialing in my dose now which is looking like it'll be around 8-9mg/week.

I've had no objectionable sides. I'm down 17lb or 6.3% in 40 days with no meaningful complaints to any of the metrics I'm tracking.


All that to say... Tirz is generally thought to be better at controlling food noise vs Reta.


I live in the state of Idaho but still west of the Rockies hence the use of PNW (Pacific NW). I'm a 65 yr old male who slowly gained weight from around the age of 35 peaking at 280#. I'm 6ft 2in. I tried doing keto and etc as my SIL got on that binge. It did nothing for me except make me focus on food 24/7. I mentioned considering GLP1 to my doctor and he was onboard. Even located a local compounding pharmacy for me. That was last March (25) and I started w tirzepitide and dropped to about 225 by Dec. Now trying to sort out a maintenance regime that works. Definitely feel the hunger/food focus come back after 2 to 3 weeks off.
Why did you take 2-3 weeks off Tirz? If tirz worked, why not stick with it this late in the game?
 
I've been using tirz 15mg/week for about 6 months but it seems to be less effective at quelling the food noise so I am considering a switch to Reta based on popular opinion here. Do I need to start at the "baby dose" of Reta to start off since I'm already hitting the GLP-1 and GIP receptors with tirz? Just interested in hearing opinions on what dose to start with and what levels people find to be effective. Thanks.

It’s obviously different for everyone, however in my experience 5 mg of Tirz definitely had a more dramatic appetite suppressing effect, and food noise was nil. Not a big dose of Tirz obviously. I started titrating down off the Tirz and up on Reta. My GI sides on Tirz were not great. Acid gut and runs. So I started Reta a bit slower. If you’re not worried about sides I’d suggest start at 2mg, I feel like jumping higher is not great. Also, if you get sides like I did I’d start much lower and titrate up .5mg per week. I only had about 30lbs total to lose so my therapeutic doses are lower. I have a chart that someone sent me that helped me calculate titrations. I’ll post it here.
 

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Why did you take 2-3 weeks off Tirz? If tirz worked, why not stick with it this late in the game?
So more details of my journey.
I moved through the doses of tirz pretty fast instead of waiting until they didn't work to bump up a level. Did 2.5 to 5.0 to 10.0 to 15.0, one month at each level. I was dropping weight at 5 but I'm a person whose weight can jump around from one day to the next (up and down) so I pushed harder. Never did too bad on the sides and slowing my GIT emptying helped my irritable bowels. I started at 280 and was shooting for 220. Got stuck at about 235 so added Cagri and that seemed to get things going again. Hit 222 but then caught a bug and went off eating for a few days so dropped below target. Since then I'm still trying to find a good maintenance regime with limited food noise and decent weight maintenance. Sitting at 228 now.
 
I was maxed out on 15mg Tirz when I hit goal, after 1 year, 5/25. I dropped the Tirz to 10mg, the following week, then the week following that I went right to Reta, I believe 1 or 1.5 intially, then to 3mg and that's were I stayed. I did stack reta w/ Cagri .250mcg, until 11/25. I dropped the Cagri stack bc I lost 15Lbs after goal weight and didn't want to loose more weight. I've haven't needed to go up on Reta despite some mild food noise, just bc I am easily satisfied and still at a caloric deficit. I don't worry about eating. I prefer to couple some behavior/ lifestyle approaches bc food noise isn't that bothersome to me, due to being easily satisfied in my maintenance. Weight is stable.
 
Am I the only one who takes both Tirz (10mg) and Reta (4mg) on the same day, at the same time? 🤣
Someone correct me if I'm wrong but isn't Reta a GIP/GLP-1/glucagon blend while Tirz is GIP/GLP-1?

So 10 mg Tirz plus 4mg Reta is really more than 10 mg Tirz plus some glucagon?

Anyway - how's that working for you? Sides?
 
Someone correct me if I'm wrong but isn't Reta a GIP/GLP-1/glucagon blend while Tirz is GIP/GLP-1?

So 10 mg Tirz plus 4mg Reta is really more than 10 mg Tirz plus some glucagon?

Anyway - how's that working for you? Sides?
10 mg Tirz plus 4mg Reta is something like 13-14mg of tirz plus some glucagon agonism. Pretty similar to me except 15.75 mg tirz and 5mg of reta, but divided into smaller doses and every 2nd day. Maybe a bit of nausea and some unpleasant skin sensations, but 1000 times better than low dose semaglutide.
 
I've been using tirz 15mg/week for about 6 months but it seems to be less effective at quelling the food noise so I am considering a switch to Reta based on popular opinion here. Do I need to start at the "baby dose" of Reta to start off since I'm already hitting the GLP-1 and GIP receptors with tirz? Just interested in hearing opinions on what dose to start with and what levels people find to be effective. Thanks.
Obviously it would be easier to give a good answer if I knew your start weight BMI etc and how much you have already lost. My approach would be to just stop the tirz and switch to anywhere between 6 and 10 mg of reta after a week.. If you had very few side effects from 15mg of tirz, the higher swapover dose might work. There is always going to be some risk of horrible side effects and the bigger the dose you swap to the higher the chance of this happening, so if older or sicker , be more careful. Reta is a bit more likely to cause increased heart rate and a bit more likely to cause skin sensation issues, and maybe a bit more nausea than the same mg dose of tirz.
You need to know that peak blood levels are about 24 hours after a dose and correspond to peak effect and peak side effects, and that it takes about a week for blood levels to drop to half that. On a given dose maximum levels will keep rising for up to 4 weeks after a dose change, which is the reason for the standard increase doses every 4 weeks.
If you want to swap to an equivalent dose of reta quickly, then the only semi safe way is smaller doses more often, so that if you do get to a dose that causes problems it will not take as long for blood levels to get back down to previous levels, compared to a single larger dose that will take a week to drop in level by half. You need to use glp plotter and put in your doses and timing and match that to your good effects like weight loss or appetite suppression and to bad effects like nausea. So you could go to 6mg , then if no side effects another 2mg after 2 days , then another 2 mg after 2 days, and you are up to 10mg already. But the faster you push it the higher the chances of unpleasant side effects. Once you are at a weekly dose you are happy with you can convert those smaller doses into one big dose once a week, which might cause more side effects or you can gradually convert the smaller doses into bigger less often doses. But double check your math and use glp plotter.
If all of this sounds confusing and complicated just swap over slowly and increase doses every 4 weeks.
 
Am I the only one who takes both Tirz (10mg) and Reta (4mg) on the same day, at the same time? 🤣

Not the same day, but close to the same doses. I take 8mg of Tirz on Thurs and 4mg of Reta on Mondays. I don't think I could handle the combined sides taking them the same day! Reta really does a number on my GI, so I like to space it apart from the tirz to give my gut a little breathing room.
 
Someone correct me if I'm wrong but isn't Reta a GIP/GLP-1/glucagon blend while Tirz is GIP/GLP-1?

So 10 mg Tirz plus 4mg Reta is really more than 10 mg Tirz plus some glucagon?

Anyway - how's that working for you? Sides?

For the 9 months that I have been injecting GLP-1s, I have never had any side effects. I know that I am extremely lucky. Nothing. Maybe all of my medical issues have de-sensitized my systems.

But I think that comes at a price of me being a very slow responder. Very slow. I mean, I have PCOS and hypothyroidism, so maybe I have a lot of shit going on that has to be overcome.
And I started out at 393 pounds (68 F) at 5'11" and nine months later, I am only at 339 pounds.

Oh well, I will continue the injections for life, just for the ancillary benefits of inflammation reduction and no more osteoarthritis knee pain and the healing of an overactive bladder. The weight loss is just the bonus.
 
I have had some really bad experiences trying to turbo titrate when switching glp1s. I would discontinue the tirz and begin Reta at 2mg for 4 weeks then 4 then 6 then 9 then 12mg, increasing every four doses. It isn’t a race. Slow and steady. Follow the study protocol.
 
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