Semaglutide vs. Tirzepatide: Side Effect Comparison

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Johnny D

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For anyone here who made the change from Sema over to Tirz — was it your experience that Tirz brought on stronger side-effects, or did you actually have fewer of them??
 
I haven't used sema myself, though every weight loss study I've seen indicates tirz comes with notably fewer side effects. A few individuals report sema works better for them, but that isn't typical.
 
Without a doubt, fewer issues. The persistent mild queasiness, sulfur burps, hiccups, unpredictable diarrhea, tiredness, and so on are gone.
 
This morning I took my first 2.5mg dose of Tirz, following a 3-month stretch on Sema during which I dropped only about 10 lbs.

My hope is that Tirz delivers better results than Sema did.

There are just 20 lbs left for me to shed, and then I'll be finished.

Wish me luck 👍
 
I have used 2mg of sema and 15mg of tirz, and tirz definitely comes with fewer side effects.

That said, even with sema, the side effects dropped a lot once the first 2-3 months had passed.
 
This morning at 8:30am I did my very first Tirz injection, and so far there is nothing at all in terms of side-effects.

Back when Sema was my medication, the day of my shot always meant feeling tired and having sore muscles during the first 24 hours. With Tirz, none of that happened. Also no nausea.

Having spent 3 months on Sema, I'm now asking myself whether my Tirz starting dose ought to be 5mg rather than 2.5mg.
 
When it comes to tirz dosing, 2.5mg carries very little risk on the side effect front, though the right call hinges largely on the semaglutide dose you came from. Coming off 2.4mg, jumping directly to 5 mg is close to completely safe. In most cases 15mg of tirz will produce fewer side effects than 2.4 of sema, but starting at that level is not something I would recommend. Should hunger still be strong and weight loss stalled, raising the dose by 2.5mg every 2 weeks would be reasonably safe, provided your prior sema dose was decent. If your sema dose was on the lower end, then titrate the tirz up more gradually, with every 4 weeks being the standard interval.

Sema and tirz both generally need 24 hours before blood levels peak, so side effects can only be judged tomorrow, and check out glp1plotter, it is very useful for understanding what blood levels of the drug do over time and makes adjusting doses easier and make more sense.

On the whole, tirz shows notably fewer gastrointestinal side effects than sema, and delivers greater weight loss, chiefly because the GIP agonism offsets the GLP-1 agonism's side effects, and aids weight loss.
 
lessthanhalf said:

When it comes to tirz dosing, 2.5mg carries very little risk on the side effect front, though the right call hinges largely on the semaglutide dose you came from. Coming off 2.4mg, jumping directly to 5 mg is close to completely safe. In most cases 15mg of tirz will produce fewer side effects than 2.4 of sema, but starting at that level is not something I would recommend. Should hunger still be strong and weight loss stalled, raising the dose by 2.5mg every 2 weeks would be reasonably safe, provided your prior sema dose was decent. If your sema dose was on the lower end, then titrate the tirz up more gradually, with every 4 weeks being the standard interval.

Sema and tirz both generally need 24 hours before blood levels peak, so side effects can only be judged tomorrow, and check out glp1plotter, it is very useful for understanding what blood levels of the drug do over time and makes adjusting doses easier and make more sense.

On the whole, tirz shows notably fewer gastrointestinal side effects than sema, and delivers greater weight loss, chiefly because the GIP agonism offsets the GLP-1 agonism's side effects, and aids weight loss.
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My Sema dose was 1mg.

Yesterday I injected 2.5mg of Tirz, yet it hardly registers.

So I'm thinking: when next week comes, should I skip the repeat 2.5mg and jump directly to 5mg Tirz?
 
As long as you're aware that when you stay on the same dose, the amount of drug in your bloodstream continues to rise over 4 weeks (which is why checking glp1plotter makes sense), then it's fairly safe. There's never a 0% chance of unexpected side effects, but typically 1mg of sema will produce significantly worse GI issues than 5mg of tirz. Since you're seeing no side effects at 2.5mg, that's a solid sign you likely won't experience much worse after raising the dose. I wouldn't jump straight to 7.5mg the following week—perhaps only after 2 or 3 weeks if there are still zero side effects; otherwise, hold off for 4 weeks.
 
lessthanhalf said:

As long as you're aware that when you stay on the same dose, the amount of drug in your bloodstream continues to rise over 4 weeks (which is why checking glp1plotter makes sense), then it's fairly safe. There's never a 0% chance of unexpected side effects, but typically 1mg of sema will produce significantly worse GI issues than 5mg of tirz. Since you're seeing no side effects at 2.5mg, that's a solid sign you likely won't experience much worse after raising the dose. I wouldn't jump straight to 7.5mg the following week—perhaps only after 2 or 3 weeks if there are still zero side effects; otherwise, hold off for 4 weeks.
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My plan was to bump it up to 5mg Tirz next week, then hold at 5mg for 4 weeks, and wait until week 5 before moving to 7.5mg
 
The 4 week figure isn't some kind of magic number — it comes down to math.

Since the half lives of the big 3 fall somewhere between 5-7 days, you've already reached 75-86% of steady state by week 2. Then week 3 lands at 88-95%. And week 4 sits at 94-98%.

Johnny D said:

lessthanhalf said:

As long as you're aware that when you stay on the same dose, the amount of drug in your bloodstream continues to rise over 4 weeks (which is why checking glp1plotter makes sense), then it's fairly safe. There's never a 0% chance of unexpected side effects, but typically 1mg of sema will produce significantly worse GI issues than 5mg of tirz. Since you're seeing no side effects at 2.5mg, that's a solid sign you likely won't experience much worse after raising the dose. I wouldn't jump straight to 7.5mg the following week—perhaps only after 2 or 3 weeks if there are still zero side effects; otherwise, hold off for 4 weeks.
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My plan was to bump it up to 5mg Tirz next week, then hold at 5mg for 4 weeks, and wait until week 5 before moving to 7.5mg
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When you're bridging from brutish Sema over to the more polished Tirz, taking frequent small doses is the safer route to quickly ramp your exposure so you can find either efficacy or sides. That's the approach I took when I went from 5mg Tirz to Reta. It worked very well toward my goals and came with minimal to no meaningful adverse sides.

My other blatherings on the subject can be found by searching for “bridge” along with my name.
 
woundcarping said:


The 4 week timing isn’t magical, it’s math.

With the big 3’s half lives ranging from 5-7 days, by the second week, you’re at 75-86% of the steady state level. Week 3 is 88-95%. Week 4 is 94-98%.

If you’re bridging from brutish Sema to more polished Tirz, frequent small doses are a safer way to rapidly ramp your exposure to find efficacy or sides. That’s what I did going from 5mg Tirz to Reta. It was very effective towards my goals and minimal to no meaningful adverse sides.

You can find my other blatherings on it by searching for “bridge” and my name.

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So, in your opinion, which one should I go with??
 
Johnny D said:


So maybe I should stay on 2.5mg, see how much weight I lose over the next few weeks, and then perhaps stay on 2.5mg for at least 4 weeks??

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What I've done — and my PCP, who's basically an insurance company puppet, is on board with it, whatever that counts for — is remain on the smallest dose that works for as long as the weight keeps coming off. The only time I've titrated up was after hitting a plateau that lasted multiple weeks. Right now I'm on 12.5mg, roughly 9 months in.
 
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