Why does it smell like eggs — sulfur burps on sema and what actually helps

S
Joined 2026
8 posts
sulfur_shrugNew Member
3/5/2026 · 9183 views

I am not exaggerating when I say my burps smell like a rotten boiled egg locker room. I want to know two things: 1) what's the mechanism, 2) what the hell actually works because Google gives me a useless list of 'stay hydrated.'

My context: 0.5mg sema, week 6. Started at 0.25 and the burps were mild. Increased to 0.5 and my partner has started fake-coughing when I exhale. It's humbling.

What I've tried:

  • Hydration — zero effect.
  • Less sulfur-rich food (cruciferous, eggs, red meat) — modest effect, burps still smelly, just less frequent.
  • Pepto Bismol before meals — actually noticeable improvement. Mechanism something about binding sulfides I think.
  • Famotidine 20mg — didn't do much for the smell, did help general GI.
  • Digestive enzymes w/ meals — placebo territory for me.

What's working for you? And does this go away or is this my life on sema now?

15 Replies

F
Joined 2026
19 posts
3/6/2026

The mechanism is real. Sema slows gastric emptying, food sits longer, sulfur-producing bacteria have more substrate and time to make hydrogen sulfide. That's the rotten-egg smell. Less food in stomach = less smell. Pepto Bismol (bismuth subsalicylate) literally binds sulfides into bismuth sulfide, which is black and inert. That's why your stool might also go dark while using it — normal.

M
Joined 2026
31 posts
3/7/2026

Smaller meals. This is the single biggest lever nobody wants to hear. If you eat 800 kcal in one sitting on sema, that food is going to hang out for hours. Split into 400 + 400 and the smell drops by half, in my experience.

S
Joined 2026
28 posts
3/7/2026

For me sulfur burps went away by week 10-12. Not gone, just not weaponized. I think the gut microbiome adapts to the slower transit over a couple months. Hang in there.

Week 14
  • Semaglutide · 1.7 mg · weekly · sub-Q
S
Joined 2026
8 posts
sulfur_shrugNew Member
3/8/2026

@fridge_protein that mechanism explanation is the most useful thing I've read all week. Thank you. Going to double down on Pepto and smaller meals and accept the black stool.

P
Joined 2026
36 posts
3/8/2026

Underrated: cut eggs and red meat for 48h before the expected peak (day 2-4 post-injection). That's when I get the worst of it. Outside that window I can eat normally. The peak window is when gastric emptying is slowest.

Q
Joined 2025
26 posts
3/9/2026

Activated charcoal caps — 500mg with the offending meal. Binds the H2S. Don't take it with your sema injection day meds or anything else you need absorbed. Works for me when I have to travel and can't avoid buffet food.

Nightshift
  • DSIP · 100 mcg · pre-bed · sub-Q
  • Epithalon · 10 mg · 10d cycles · sub-Q
S
Joined 2026
115 posts
3/10/2026

Activated charcoal does bind non-specifically. So yes it'll bind sulfides and also your multivitamin and whatever medication you took two hours ago. Fine as rescue, bad as routine.

J
Joined 2026
27 posts
3/10/2026

My partner made me read this thread out loud over breakfast as punishment. For the record: hydrogen sulfide burps went away at week 8 for me, held there ever since on 1.0.

C
Joined 2026
25 posts
3/12/2026

Zofran for the nausea that tends to come WITH the sulfur burps for me. Doesn't help smell, does help being able to function during the worst days.

S
Joined 2026
8 posts
sulfur_shrugNew Member
3/12/2026

Update a week in: Pepto before each meal + meal splitting has cut it 70%. Partner no longer fake-coughs. Marriage saved by this thread.

F
Joined 2026
19 posts
3/13/2026

@sulfur_shrug good outcome. One more tip for when it's back: peppermint tea post-meal genuinely helps motility a bit. Not magic but real.

B
Joined 2026
22 posts
3/14/2026

Wild how specific these side effects get. Filed away for when I start.

H
Joined 2025
205 posts
hexaclinicContributor
3/15/2026

Secondary point — if sulfur burps are accompanied by upper abdominal pain that doesn't go away, get labs (lipase, amylase) and don't wait. Most sulfur burps are benign gastric slowdown. Rarely they're a signal of something that needs eyes on it.

Q2 stack
  • CJC-1295 no DAC · 100 mcg · pre-bed · sub-Q
  • Ipamorelin · 200 mcg · pre-bed · sub-Q
  • BPC-157 · 500 mcg · 2x/day · sub-Q
S
Joined 2026
36 posts
slow_loseMember
3/17/2026

I will say — sulfur burps are the symptom that almost made me quit. Reading people say it goes away at week 8-12 kept me on. It did. Worth pushing through if you can.

T
Joined 2026
8 posts
thread_saverNew Member
3/19/2026

Saving. This thread is going to help more people than any label insert.

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