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What kind of side effects can you expect on Wegovy, and when? It’s complicated. But I did crap my pants once.
Everyone is different
Everyone reacts to drugs differently, but with Wegovy it really seems to be all over the map.
Some people get no side effects, some people seem to get all of them. It’s really unfair.
This is where I remind you again that I’m not a doctor, or a scientist. In fact I have zero medical training at all (unless you count watching hundreds of hours of M*A*S*H and ER, which you absolutely shouldn’t). Nothing that I say should be taken as medical advice. I’m simply recounting my own experiences on Wegovy (I’ve been on it for about six months), and what I’ve read and heard from other users.
Expecting the worst
I’d read a lot of horror stories about side effects from Wegovy and Ozempic (they both contain the same drug, Semaglutide, but Wegovy is approved for weight loss, and Ozempic is approved to treat diabetes). I’d hit some subreddits to try to find out what taking Wegovy was really like, mostly r/WegovyWeightLoss and r/Semaglutide.
Spend some time on the Wegovy-related boards on reddit, and you might come away thinking that everyone on the medication has a ton of side effects. But keep in mind that people don’t tend to post on those boards just to say “Hi, I’m on Wegovy and not having any side effects.” Many of the people posting are either having issues and looking for answers, or warning people.
Still, looking through the side-effect questions can give you a good idea of the possibilities. And there do seem to be a lot of people who have bad side effects, mostly nausea, constipation, diarrhea, and fatigue.
Diarrhea and constipation
I wasn’t too worried about diarrhea or constipation. On one hand, I don’t have a gall bladder anymore and am lactose intolerant, but I do eat a lot of dairy (Lactaid really helps, BTW, but make sure you’re getting the individually-wrapped Fast Act tablets—they’re three times more powerful than the ones that come in a bottle). Both of those things can cause diarrhea.
On the other hand, before Wegovy I was already on two medications that can cause constipation (at one point, before I knew what was going on, it was so bad that I ended up needing minor surgery, but that’s a horror story for another day).
So between all of those things, I’d gotten used to balancing everything using Colace 2-in-1 when I needed it.
In the end (pun intended), being on Wegovy didn’t give me any problems in that area. Or did it? Like I said, I already have so many other things going on in my digestive system, I’m not sure I would notice something else. (Oh, except that ONE time…more on that later.)
But a lot of people have BIG problems with one or the other, so it’s something to be aware of and prepared for.
Nausea
Throwing up, or even just feeling nauseated, was what I was really worried about it. I hate that feeling more than pretty much anything. I’d read accounts from people who had to take Zofran they were throwing up so much.
That would not have been worth it to me. I think I would have given it about a week, and then I would have given up.
However, I’ve never thrown up from Wegovy, and have felt nauseated exactly three times. And all three happened after I overate.
Overeating on Wegovy
I mentioned in my last post that with Wegovy, I stop eating when I’m full. But there’s a little more to it than that.
My hunger, and the amount that I eat, is not the same every day. For the first couple of days after I take my weekly injection, I eat very little. I’m just not hungry or interested in food.
There have actually been a few times the day after a shot when I just didn’t feel right, tired and light-headed, with a dull ache in my stomach. And then I would realize that my body was actually starving, I just wasn’t feeling hungry. I ate a little and immediately felt fine.
Then, as the week progresses and I have less and less Semaglutide in my system, I get hungrier and I eat more. This is why I take my injections on Mondays: by the weekend, when I’m more likely to be making a big meal for my family or going out to eat, I can eat more! Still nowhere near what I used to pack in, but more.
Wegovy and period hormones
However, when the end of my Wegovy week coincides with when I’m about to get my period, that old feeling of wanting to just stuff myself with food creeps back in. So, it’s happened about once a month so far, at least for the last few months (it took a while for the drug’s effects to ramp up).
And it sucks.
The first time it happened, I’d just made potato salad. I make great potato salad, and I hadn’t made it in a while. It was still warm, which isn’t even how I like to eat it; it’s so much better after it’s been sitting in the fridge for a day.
But I started eating, and kept going, and going. It was like I didn’t even realize what was happening. And then I snapped out of it, and felt absolutely awful. I was sweating, and nauseated, and eventually I just gave up and climbed into bed until it passed, which took a couple of hours.
The next two times weren’t nearly as bad, because my guard was up a bit. I did overeat, but nowhere near as much, and the nausea passed in just a few minutes. The second time was toast with peanut butter, and the third time was half a sleeve of Thin Mints, which I used to consider a small serving.
And now that I can predict when it’s likely to happen, I’m really going to try to control myself.
I’m super lucky. I can eat a reasonable amount of any food. I’ve read about people who get nauseated if they eat any fried or fatty foods, or foods with a lot of sugar. Some people can’t tolerate alcohol any more, or coffee, and others have to stay away from dairy.
And of course, there are a lot of people who just feel sick no matter what they eat.
Fatigue
I haven’t experienced this one either, thank goodness. Some people say they’re so lethargic they can barely get out of bed. Is it a matter of nutrition? Are they throwing up or having diarrhea so much that they simply don’t have enough food in them to run on? Are they eating crap and getting absolutely no nutrients? I have no idea. But it sounds awful.
Other weird side effects
I’ve seen lots of posts about “sulfur burps,” headaches, heartburn, metallic taste in mouth, super-sensitive skin, hair loss, and more. Of course, it’s impossible to know if they’re all directly related to Wegovy, but when enough people report the same thing, it’s something to think about and look out for.
The time I sharted
So once again, I’m going to say up front that I am extremely lucky. If this had happened in public, it would have been mortifying. And there are some stories like that on reddit (if you want to have some fun, search the Semaglutide and Wegovy subreddits for phrases like “pooped pants” or “never trust a fart.”).
But it happened under the best possible circumstances. And I didn’t even connect it to Wegovy for several weeks.
After I’d been on Wegovy for a couple of months, I was seeing my primary care doctor for something unrelated, and I added it to my chart as a medication I was taking. My doctor asked me if I’d had any side effects, and I said no. She said that if I hadn’t had them by then, I wouldn’t get any.
But that didn’t turn out to be true. This happened when I was four months in.
Going up a dose
I had gone up from 1mg to 1.7mg the week before. I’d been kind of watching out for side effects with the increased dose, but I’d been on it for so long with no issues that my guard was completely down, especially after what my doctor had said.
It was the morning, and I had my period. So I was pretty much wearing an overnight period diaper (seriously, these things are HUGE, but they work—and apparently for more than just periods!!).
Basically, I thought I had to fart, and since I was in the comfort and privacy of my own home, I did…but that wasn’t all I did.
I knew immediately what had happened, and ran to the bathroom. Thanks to the overnight pad, there was no mess to clean up, the whole thing just went in the garbage (and then right outside, because I was afraid it was going to smell up the bathroom and I’d have to explain it!).
But I was hugely embarrassed, and wondering why it had happened. I did feel a little “off” but had figured it was just my period. Now I was wondering if I was coming down with something. I’d never had uncontrollable diarrhea before, but I’d come close almost every time I’d had a bad stomach bug. Was that it? It seemed like a weird time of the year (summer) for Norovirus, or maybe I had COVID?
But by that afternoon I felt totally normal, so I thought maybe I’d just eaten something bad, and forgot all about it.
And I’m really glad that it worked out that way, because if I’d connected it to Wegovy right away, I probably would have freaked out. I would have been so worried that it was going to happen again.
The second shot
I’d been going back to the reddit boards every once in a while, and a few weeks after “the incident” I saw something interesting. It was a post from someone saying that they always threw up for a couple of days after they moved up to a new dose, but not until the second shot of that dose.
They were wondering why that was. Wouldn’t it make more sense if it happened when they first increased the dose?
And a lot of other people commented that they also had their worst side effects after the second shot of a new dose.
Why?? That made no sense to me. But I still wasn’t making the connection with what had happened to me.
And then a lightbulb went off, and I opened up my calendar to see when my last period had been, and when I’d started the 1.7mg dose, and when “the incident” had happened.
Yup, it had been a day or two after my second dose of 1.7mg. WTF???
I started googling madly, trying to figure it out. I thought I’d found the answer in the elimination half-life of Semaglutide.
What is a drug’s half life?
A drug elimination half-life is how long it takes your body to get rid of half of the drug. (Again, I’m going to point out that I am not a doctor or scientist, just somebody who reads a lot; don’t rely on me for info!)
Half life can vary based on things like a patient’s age, metabolism, kidney function, or other factors, so keep in mind it isn’t exact, but it’s a place to start.
The drug elimination half-life of Semaglutide
The drug half-life for Semaglutide is seven days, give or take. This means that after seven days, about half of your last injection is still in your system. Over the next seven days, it decreases by half again. If you don’t take another dose, it takes about five weeks for all of it to be gone (there’s still a little left, but not enough to matter).
But if you keep taking that same dose every seven days, then after four or five weeks, there will be a steady amount of Semaglutide in your system week-to-week (although it will still fluctuate within each week).
So basically, a month after you start taking, say, a 1mg dose, you’ll have 2mg of the drug in your system each week, because of what’s left over from your last four or five weeks of shots.
I really thought that this was the key. Maybe because of how much stays in your system, you have the biggest increase after the second shot of a new dose, and your system can’t handle it!
But I did the math, and it didn’t work out. The biggest percentage increase, by far, is always going to be when you move up from one dose to a higher dose. Yes, you’ll have even more of the drug in you after you take the second shot, but it shouldn’t be as much of a shock to your system as when you moved up to a bigger dose.
There are many things about drug half-life that I can’t even begin to understand or take into account, like plasma concentration, time to maximum concentration, etc.; I only understand the very basics of drug half-life. So maybe there is something there. Maybe some of us just clear the drugs from our systems much slower than other people. I do have trouble getting rid of anything, why should this be any different?
So, this one has me stumped. But there seem to be a lot of us who had our worst side effects after the second shot of a new dose. Plan accordingly.
The bottom line
It’s just really, really hard to predict how you’re going to react to Wegovy. And just when you think you’re past the point where you would have gotten side effects, bam, they can appear (but at least there seems to be a pattern).
The only things I can suggest are ramping up your dosage very slowly, watching out for any foods that might trigger digestive issues, and taking your injections when you’re supposed to.
And never, ever, trust a fart.