How quickly did effects show up after your first dose?

lil ghost

lil ghost

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not sure whether this is placebo or if my body just reacts fast, but under 24 hours after my very first tirz injection I've got zero appetite. I went with a low starting dose too (2mg), because my BMI sits toward the lower side of the "healthy" range. maybe I'm tricking myself into believing I'm not hungry, yet it honestly feels like I'm stuffed even though I've barely eaten today.

this is my first experience with any peptide at all, so I've got nothing personal to measure it against. just wondering whether others noticed things happening immediately, or whether I'm kidding myself and/or some kind of outlier.
 
A window like that isn’t unusual. In my model, Tmax comes out to 24 hours.

Back when I began, I went hunting for this exact kind of answer too—wondering whether it was all in my head or whether things had genuinely kicked in by around 12 hours.
 
Reta hit me pretty fast. Going into that first shot, my headspace was negative and I figured it wouldn't do anything. By the following day I was dialed in, sticking to clean eating and the same diet I follow now, with zero pull toward sugar. My dad, though, needed 2-3 weeks before the food noise went away. Funny how differently we respond, even when it's the same vial.
 
For me, I can begin to notice something roughly 24 hrs following a dose, and it reaches its highest point around 48 hrs after taking it.
 
For me, it kicks in really quickly — an hour or 2 at most. Injecting into your stomach makes the sensation stronger. By the following day you ought to notice it clearly 🙂 and as it accumulates in your system, that feeling stays with you constantly, even at the point when your next dose is due.
 
With tirz, once I take a shot following a break, or when I increase my dosage, I can count on explosive diarrhea and projectile vomiting hitting exactly at the 36 hour point. That said, the appetite suppression is already there when I get up in the morning (I inject myself just before going to sleep).
 
I notice a pattern in posts from folks who begin GLP's at low doses and aren't carrying much extra weight — they often report fast or strong reactions at those low doses. That gets me thinking: could this kind of response be more common in people with less excess weight, compared to those with more to lose, who likely have more serious metabolic and hormonal issues — higher insulin and leptin resistance, and so on? In my own case, after dropping 70kg and dealing with side effects from a low dose of ozempic, I was able to push tirzepatide up to 15mg within a month and still felt somewhat hungry. (I used small, frequent doses to lower the chance of severe side effects.)
 
lessthanhalf said:

I notice a pattern in posts from folks who begin GLP's at low doses and aren't carrying much extra weight — they often report fast or strong reactions at those low doses. That gets me thinking: could this kind of response be more common in people with less excess weight, compared to those with more to lose, who likely have more serious metabolic and hormonal issues — higher insulin and leptin resistance, and so on? In my own case, after dropping 70kg and dealing with side effects from a low dose of ozempic, I was able to push tirzepatide up to 15mg within a month and still felt somewhat hungry. (I used small, frequent doses to lower the chance of severe side effects.)
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I appreciate you posting that, LTH. It's been a letdown that my own experience hasn't matched that amazing Miracle Drug Experience ™. I'm only at the beginning of the dosing schedule, yet I've noticed nothing at all. My appetite is unchanged, and so is everything else.
 
the next day, it seemed like all my food was going down as one giant lump LMFAO. i got full faster. food didn’t hold as much interest for me. it was amazing!!! normally i have intense food noise
 
For me, the effects showed up the following day. I was at work, taking my lunch break, and I managed to finish only 50% of what I'd brought since I felt full. I recall feeling oddly let down, and a bit puzzled as well. All those years I'd been eating too much, and it hit me that perhaps this is how people normally eat. After 3.5 months, I'm now accustomed to smaller portions. At times I have to push myself through some meals just to hit my protein target for that day. My advice: don't hurry to bump up your dosage.
 
Roughly 12 months after dropping around 70kg, I began Ozempic. The very first change I picked up on was that even a modest portion left me so stuffed I couldn't clean my plate. Up until that point, I don't think that sensation had ever happened to me.
 
lil ghost said:

not sure whether this is placebo or if my body just reacts fast, but under 24 hours after my very first tirz injection I've got zero appetite. I went with a low starting dose too (2mg), because my BMI sits toward the lower side of the "healthy" range. maybe I'm tricking myself into believing I'm not hungry, yet it honestly feels like I'm stuffed even though I've barely eaten today.

this is my first experience with any peptide at all, so I've got nothing personal to measure it against. just wondering whether others noticed things happening immediately, or whether I'm kidding myself and/or some kind of outlier.
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I injected my initial 2mg of R. For the first bit…nothing at all. I figured it might be fake.

But around days 2–3, a change became apparent. I wasn't truly hungry, nor truly full, just… neutral. My eating seemed regulated, as if I could quit once I genuinely had enough.

After that, on the following two mornings I got up near 4am with head pain (which never occurs for me), despite being hydrated and keeping up with electrolytes.

So it does look like it's doing something… just not in the way I pictured 😅

I value threads like this; it helps to read about other people's early experiences.

Best of luck!

Danger1212
 
Last week I took a low dose for the first time ever, and within about 30 minutes the effects hit me — almost right away. It felt like a fog made of nonstop food noise lifted all at once. For the remainder of that day, staying inside my calorie deficit was ridiculously simple. At one point I picked up a snack I'd already planned out, then midway through I forgot to finish it. That never happens to me. Later, dinner was a take it or leave it situation. Is this what it's like for naturally thin people, going through life this effortlessly!? Incredible.

Of course, since the starting dose was low, the food noise and real hunger began creeping back within a few days. I can't wait to eventually titrate up to whatever dose holds up across the entire week.
 
cloratheshadow said:

For me, it kicks in really quickly — an hour or 2 at most. Injecting into your stomach makes the sensation stronger. By the following day you ought to notice it clearly 🙂 and as it accumulates in your system, that feeling stays with you constantly, even at the point when your next dose is due.
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Stomach injections aren't my thing—they sting more, and I'd rather keep discomfort to a minimum. Outer thighs are where I inject, and the onset feels just as fast as it did with stomach shots. Plus, I'm more at ease that way.
 
Following my initial injection, it honestly felt like it kicked in right away. I took the shot 1.5 hr ahead of when I normally eat breakfast, and I didn't end up eating until 3 hrs later — purely because the clock had already hit 11 AM. Hunger just wasn't there.

With the second injection, though, the full effect didn't arrive until day 2.

My 3rd shot is scheduled for this Wednesday, so I'll find out what happens then.
 
I've spent the last month at just 2.5mg. My injection goes in around midday, and by late afternoon or early evening I can tell it's working — hunger cues are toned down. The strongest effect, though, always lands the following day or morning. So for me the window from the first few hours up to the first 24 hours is consistently when I notice it most. And like others have said, it keeps building as it stacks with each later dose.
 
I began more than a year back at 2.5mg. Within minutes, I noticed something. Sure, it feels strange when you've spent 60 years thinking about food. Now at 19.5mg, the onset is somewhat more gradual. During one of the initial doses at 15mg, I felt a slight buzz. I'm still unclear about what occurred?
 
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