Peptides for ADHD: separating signal from TikTok noise

What did @notdony actually say?

Pretty straightforward self-report: after bumping their dose of "red up" (almost certainly retatrutide, a GLP-1/GIP/glucagon triple agonist) to 2mg, they started vomiting every time they took Adderall. Their explanation? They looked it up and figured out they needed to eat first, because their old habit of skipping food or eating while already medicated wasn't cutting it anymore.

This is a real, recognizable problem that shows up repeatedly in GLP-1 user forums and increasingly in clinical notes. The creator isn't speculating wildly here. They experienced something, investigated it, and landed on a plausible explanation. That deserves credit before we pick it apart.

Does the science back this up?

Yes, largely. GLP-1 receptor agonists slow gastric emptying significantly, and at higher doses that effect becomes more pronounced. Nausea and vomiting are the most common dose-dependent adverse effects reported across the GLP-1 class.

A 2023 phase 2 trial of retatrutide by Jastreboff et al. published in the New England Journal of Medicine reported nausea in roughly 45-65% of participants at higher doses, with vomiting in a substantial subset, particularly during dose escalation. The mechanism is well established: GLP-1 receptors in the gut and brainstem area postrema slow motility and trigger nausea signals. Taking a stimulant medication like Adderall on an empty stomach is already a known irritant to gastric mucosa. Stack that on top of significantly slowed gastric emptying and you have a reliable recipe for vomiting. The food-first strategy the creator landed on is the same recommendation gastroenterologists and prescribing clinicians give to GLP-1 patients routinely.

What did they get wrong (or right)?

They got the core mechanism right intuitively, even if they didn't name it. Eating before taking Adderall on a GLP-1 agent is genuinely reasonable advice. What they got wrong is the framing of self-adjusting a 2mg dose of retatrutide without any mention of clinical oversight.

Retatrutide is not FDA-approved. It exists as a compounded peptide in the gray market. Dose titration on a triple agonist without medical supervision is not a minor issue. The nausea-vomiting cycle at higher doses can lead to dehydration, electrolyte imbalance, and in people taking stimulants, cardiovascular stress. The creator presents "upping my dosage" as casual, and that framing is genuinely problematic regardless of how good their self-research is. There is also no mention of telling a prescriber about the Adderall interaction, which is exactly the kind of thing a clinician managing both medications needs to know.

What should you actually know?

GLP-1 class agents slow gastric emptying, and that effect compounds with dose. This is not a quirk of "red up" specifically. It is a class effect. If you are on any GLP-1 agent and taking oral medications that depend on gastric absorption timing, that timing changes. Some medications become less effective. Others sit in the stomach longer and cause irritation or vomiting.

Amphetamine salts like Adderall are already gastric irritants on an empty stomach in a meaningful portion of users. The combination with a GLP-1 agent at dose escalation is not studied in formal trials, so anyone telling you exactly what to expect is extrapolating. The eat-first strategy is reasonable but it is not a complete solution. Persistent vomiting after dose increases should be a signal to contact your prescriber, not a problem to troubleshoot alone via search engines. If you are managing ADHD medication and a GLP-1 peptide simultaneously, that stack warrants actual clinical coordination, not just a Reddit thread.

Should you copy this approach?

No. Self-titrating a compounded, non-FDA-approved triple agonist peptide and managing the gastrointestinal side effects by changing your eating habits around a controlled stimulant is not a template anyone should replicate without clinical supervision. The creator's troubleshooting instinct was reasonable. The broader setup they are describing is not something to treat as a casual lifestyle protocol.

• Retatrutide is under investigation, not approved for any indication.
• Dose escalation decisions on GLP-1 class agents should involve a prescriber who knows your full medication list.
• Nausea and vomiting at higher doses are expected, not a sign you just need to adjust your meal timing.