Tirz to Reta Switch: Finding an Effective Starting Dose

Wallydog

Wallydog

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I've been on tirz at 15mg/week for roughly 6 months now, but it's not doing as much to quiet the food noise anymore. Seeing how often Reta comes up here, I'm thinking about making the change. Since tirz already has me activating the GLP-1 and GIP receptors, is it necessary to begin Reta at the "baby dose"? I'd like to hear what starting dose others would suggest and which doses they've found actually work. Thanks.
 
On Tirz I climbed to 12.5 mg / week, and then it quit doing anything for me. The side effects were brutal, so I switched over to Reta. My starting point was 2 mg, then I went up by another 2 mg / week until I reached 8 mg. These days I take 4 mg every 84 hours. When my next kit shows up, I'll move to 5 mg every 84 hours for roughly a month, after which I may try 6.

Reta gives me stronger hunger suppression than Tirz did, though I'm not sure whether that matches what most people on Reta go through.

Should Reta ever stop Reta-ing, I'd likely bring Cagri into the mix.
 
Not_Your_Dad said:

On Tirz I climbed to 12.5 mg / week, and then it quit doing anything for me. The side effects were brutal, so I switched over to Reta. My starting point was 2 mg, then I went up by another 2 mg / week until I reached 8 mg. These days I take 4 mg every 84 hours. When my next kit shows up, I'll move to 5 mg every 84 hours for roughly a month, after which I may try 6.

Reta gives me stronger hunger suppression than Tirz did, though I'm not sure whether that matches what most people on Reta go through.

Should Reta ever stop Reta-ing, I'd likely bring Cagri into the mix.
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The general consensus seems to be that tirz handles appetite suppression more effectively.
 
CNCCurrency said:

Not_Your_Dad said:

On Tirz I climbed to 12.5 mg / week, and then it quit doing anything for me. The side effects were brutal, so I switched over to Reta. My starting point was 2 mg, then I went up by another 2 mg / week until I reached 8 mg. These days I take 4 mg every 84 hours. When my next kit shows up, I'll move to 5 mg every 84 hours for roughly a month, after which I may try 6.

Reta gives me stronger hunger suppression than Tirz did, though I'm not sure whether that matches what most people on Reta go through.

Should Reta ever stop Reta-ing, I'd likely bring Cagri into the mix.
Click to expand...
The general consensus seems to be that tirz handles appetite suppression more effectively.
Click to expand...
That matches the impression I've gotten around here as well. For me, Reta seems to work on the mental side — it kills the desire to eat — while Tirz kept me from eating physically, through slower gastric transit and so on. Even so, the same tug toward food was always there. On Reta, that tug is gone.
 
When I moved over from Tirz to Reta, my Tirz schedule was 2.5mg taken 2x per week. Because I was nervous about side effects, I broke the transition into roughly 12 smaller shots (each between 1-2.5mg) spread across 15 days. The goal was to raise my blood levels fast without blowing past the target and getting stuck dealing with a rough ride. From what I read, GCGR signaling — the thing I was after — tends to be consistently activated once you reach a steady state of about 6-8mg/week.

While bridging, I also used 2 extra Tirz doses (2.5mg and 2mg) on day 4 and day 11 to keep food noise in check.

Come Saturday, it will be 6 weeks since the bridge began. I've given myself 19 shots for a total of 53-54mg. Right now I'm fine-tuning the dose, and it looks like it will land near 8-9mg/week.

Nothing unpleasant has come up. Over 40 days I've lost 17lb, which is 6.3%, and none of the metrics I monitor have raised any real concerns.

So the takeaway is... the common view is that Tirz handles food noise better than Reta.

Wallydog said:


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.

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What made you stop Tirz for 2-3 weeks? If Tirz was doing its job, why switch away from it at this point?
 
Wallydog said:

I've been on tirz at 15mg/week for roughly 6 months now, but it's not doing as much to quiet the food noise anymore. Seeing how often Reta comes up here, I'm thinking about making the change. Since tirz already has me activating the GLP-1 and GIP receptors, is it necessary to begin Reta at the "baby dose"? I'd like to hear what starting dose others would suggest and which doses they've found actually work. Thanks.
Click to expand...

Everyone reacts differently, of course, but for me 5 mg of Tirz gave a much stronger appetite-suppressing effect, and the food noise disappeared completely. That isn't a large Tirz dose, clearly. I began lowering the Tirz while raising the Reta. My GI side effects on Tirz were rough: acid stomach and diarrhea. Because of that, I brought Reta in more gradually. If side effects aren't a concern for you, my recommendation would be to begin at 2mg, since I think a bigger jump isn't a good idea. And if you do end up with sides the way I did, I'd begin at a much lower amount and increase by .5mg weekly. I only needed to lose around 30lbs altogether, so my therapeutic doses sit lower. Someone sent me a chart that helped me work out titrations. I'll share it in this thread.
 
woundcarping said:

When I moved over from Tirz to Reta, my Tirz schedule was 2.5mg taken 2x per week. Because I was nervous about side effects, I broke the transition into roughly 12 smaller shots (each between 1-2.5mg) spread across 15 days. The goal was to raise my blood levels fast without blowing past the target and getting stuck dealing with a rough ride. From what I read, GCGR signaling — the thing I was after — tends to be consistently activated once you reach a steady state of about 6-8mg/week.

While bridging, I also used 2 extra Tirz doses (2.5mg and 2mg) on day 4 and day 11 to keep food noise in check.

Come Saturday, it will be 6 weeks since the bridge began. I've given myself 19 shots for a total of 53-54mg. Right now I'm fine-tuning the dose, and it looks like it will land near 8-9mg/week.

Nothing unpleasant has come up. Over 40 days I've lost 17lb, which is 6.3%, and none of the metrics I monitor have raised any real concerns.

So the takeaway is... the common view is that Tirz handles food noise better than Reta.

Wallydog said:


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.

Click to expand...
Click to expand...
What made you stop Tirz for 2-3 weeks? If Tirz was doing its job, why switch away from it at this point?
Click to expand...
Here's a fuller picture of how it went for me.

Rather than holding at each level until it stopped working, I climbed the tirz doses quickly. Went 2.5, then 5.0, then 10.0, then 15.0 — a month at every step. At 5 I was already losing, but my weight swings day to day (both directions), so I figured I should push. Side effects never got too rough, and the slower GIT emptying actually settled my irritable bowels. My starting weight was 280 and my goal was 220. I stalled around 235, so I brought in Cagri, which appeared to restart things. I reached 222, but then picked up a bug and couldn't eat for a few days, which took me under goal. Since then I've been hunting for a maintenance routine that keeps food noise low and weight steady. Right now I'm at 228.
 
When I reached my goal, I had been on the maximum 15mg of Tirz for 1 year, as of 5/25. The next week I lowered my Tirz dose to 10mg, and then the week after that I switched straight over to Reta — I think it was 1 or 1.5 to start, then I moved up to 3mg, which is where I've remained. I stacked Reta with Cagri .250mcg until 11/25. I stopped the Cagri stack because I had dropped 15Lbs below my goal weight and didn't want to keep losing. Even with a bit of mild food noise, I haven't had to increase my Reta dose, simply because I get satisfied easily and I'm still eating at a caloric deficit. Eating isn't something I stress about. I like to pair in some behavioral and lifestyle strategies, since food noise doesn't really bother me much — I'm satisfied easily while maintaining. My weight has stayed steady.
 
QueenMuntha said:

Is it just me, or do others also pin Tirz (10mg) and Reta (4mg) together on one day and one moment? 🤣
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If I'm mistaken, someone please set me straight: Tirz targets GIP/GLP-1, whereas Reta adds glucagon to that same GIP/GLP-1 mix, right?

That would mean 10 mg Tirz alongside 4mg Reta delivers more than just 10 mg Tirz with a bit of glucagon added?

Regardless - what results are you seeing, and how are the sides treating you?
 
Wallydog said:

QueenMuntha said:

Is it just me, or do others also pin Tirz (10mg) and Reta (4mg) together on one day and one moment? 🤣
Click to expand...
If I'm mistaken, someone please set me straight: Tirz targets GIP/GLP-1, whereas Reta adds glucagon to that same GIP/GLP-1 mix, right?

That would mean 10 mg Tirz alongside 4mg Reta delivers more than just 10 mg Tirz with a bit of glucagon added?

Regardless - what results are you seeing, and how are the sides treating you?
Click to expand...
A stack of 10 mg Tirz alongside 4mg Reta ends up feeling roughly like 13-14mg of tirz with added glucagon agonism. That is close to what I run, only mine is 15.75 mg tirz with 5mg of reta, split across smaller shots and taken every 2nd day. There may be slight nausea plus odd skin feelings, yet it beats low dose semaglutide by 1000 times.
 
Wallydog said:

I've been on tirz at 15mg/week for roughly 6 months now, but it's not doing as much to quiet the food noise anymore. Seeing how often Reta comes up here, I'm thinking about making the change. Since tirz already has me activating the GLP-1 and GIP receptors, is it necessary to begin Reta at the "baby dose"? I'd like to hear what starting dose others would suggest and which doses they've found actually work. Thanks.
Click to expand...
To give a solid recommendation, I'd really need details like your starting BMI and how much weight you've dropped so far. That said, here's how I'd handle it: ditch the tirz entirely, wait a week, then begin reta somewhere in the 6 to 10 mg range. If 15mg of tirz gave you almost no side effects, jumping in at the upper end of that range could be fine. Side effects can always hit hard, and the odds go up with whatever dose you jump to, so anyone older or in worse health should err on the side of caution. Compared with the same mg of tirz, reta tends to trigger a faster heart rate a little more often, skin tingling sensations a little more often, and perhaps slightly more nausea.

Key point: blood levels hit their max roughly 24 hours after injecting, and that's when you feel the strongest effects and the worst side effects. It takes around a week for those levels to fall by half. After any dose change, peak levels continue climbing for as long as 4 weeks, which explains why the usual schedule bumps the dose every 4 weeks.

If you're set on reaching an equivalent reta dose fast, the only somewhat safe route is taking smaller amounts more frequently. That way, if a dose causes trouble, your blood levels come down quicker than they would after one big shot, which takes a week just to halve. Plug your doses and schedule into glp plotter and line that up against both the good outcomes (weight loss, appetite suppression) and the bad ones (nausea). For example: start at 6mg, and if nothing bad happens, add another 2mg 2 days later, then another 2 mg 2 days after that, and you're already at 10mg. The quicker you ramp, though, the greater the risk of nasty side effects. Once you land on a weekly dose you're comfortable with, you can either consolidate those small doses into one weekly shot, which may worsen side effects, or slowly shift toward larger doses taken less often. Either way, verify your calculations and rely on glp plotter.

If this all feels too confusing and complex, just make the switch gradually and raise the dose every 4 weeks.
 
QueenMuntha said:

Is it just me, or do others also pin Tirz (10mg) and Reta (4mg) together on one day and one moment? 🤣
Click to expand...

I don't take both on one day, though the amounts are pretty similar. Every Thursday I'm on 8mg of Tirz, and then Mondays I do 4mg of Reta. If I took them together, the stacked side effects would be too much for me! My GI tract gets hit hard by Reta, so separating it from the tirz gives my stomach some recovery time.
 
Wallydog said:

QueenMuntha said:

Is it just me, or do others also pin Tirz (10mg) and Reta (4mg) together on one day and one moment? 🤣
Click to expand...
If I'm mistaken, someone please set me straight: Tirz targets GIP/GLP-1, whereas Reta adds glucagon to that same GIP/GLP-1 mix, right?

That would mean 10 mg Tirz alongside 4mg Reta delivers more than just 10 mg Tirz with a bit of glucagon added?

Regardless - what results are you seeing, and how are the sides treating you?
Click to expand...

Over the 9 months I've spent injecting GLP-1s, side effects have never shown up for me. I realize how fortunate that makes me. Not a single one. It's possible my various medical conditions have left my body less reactive.

The trade-off, though, seems to be that I respond very slowly. Extremely slowly. With PCOS and hypothyroidism in the mix, there may be plenty of obstacles that need to be pushed past.

My starting point was 393 pounds (68 F) at 5'11", and after 9 months I've only reached 339 pounds.

Regardless, I'll keep injecting for life, if only for the extra perks: less inflammation, no more osteoarthritis knee pain, and an overactive bladder that has healed. The weight loss is simply a bonus.
 
When I've jumped between different glp1s and pushed the dose up too fast, things went badly for me. My approach would be to stop the tirz, then start Reta at 2mg and hold there for 4 weeks, then move to 4, then 6, then 9, then 12mg, with each step lasting four doses. There's no need to rush it. Take it slow and consistent. Stick with the study protocol.
 
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