Comparison
N-Acetyl Cysteine vs Sermorelin
Side-by-side of N-Acetyl Cysteine and Sermorelin. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
N-Acetyl Cysteine
NAC supplement benefits cover glutathione synthesis, liver and antioxidant support, and hangover recovery. Evidence strongest at 1200-2400 mg/day.
Sermorelin
Sermorelin peptide therapy uses a 29-amino-acid GHRH analog to raise endogenous GH. Dosing, half-life, sermorelin vs ipamorelin, and safety.
Effects at a glance
N-Acetyl Cysteine
- •Replenishes intracellular glutathione by supplying cysteine, the rate-limiting amino acid for synthesis
- •First-line antidote for acetaminophen toxicity, restoring hepatic glutathione before fulminant injury occurs
- •Reduces sputum viscosity in chronic bronchitis and COPD at 600 to 1200 mg/day over months
- •Modest symptom reductions in OCD and trichotillomania at 1200 to 2400 mg/day across small RCTs
- •Mixed evidence for psychiatric adjunct use in bipolar depression and schizophrenia negative symptoms
- •Inhaled forms can trigger bronchospasm in active asthma; oral use is the standard biohacker route
Sermorelin
- •Synthetic 29-amino-acid GHRH fragment; FDA approved 1997 for pediatric GH deficiency as Geref
- •Voluntarily discontinued by Serono in 2008 for commercial reasons; not safety-related
- •Compounded by 503A/503B pharmacies for off-label adult anti-aging and body-composition use
- •Produces physiologic pulsatile GH release; ~10 to 20 minute plasma half-life
- •Standard anti-aging clinic protocol: 200 to 500 mcg subcutaneously pre-bed, often with ipamorelin
- •Banned by WADA under S2 (peptide hormones, growth factors)
Side-by-side
| Attribute | N-Acetyl Cysteine | Sermorelin |
|---|---|---|
| Category | supplement | peptide |
| Also known as | NAC | Sermorelin acetate, GRF 1-29, Geref, GHRH (1-29) NH2 |
| Half-life (hr) ↗ | 5.6 | 0.25 |
| Typical dose (mg) ↗ | 1200 | 0.3 |
| Dosing frequency | 1 to 3 times daily, split dosing preferred | 1-2x daily |
| Routes | oral, iv | subcutaneous |
| Onset (hr) | 1 | 0.25 |
| Peak (hr) | 2 | 0.5 |
| Molecular weight | 163.19 | 3357.88 |
| Molecular formula | C5H9NO3S | C149H246N44O42S |
| Mechanism | Deacetylated to cysteine, the rate-limiting precursor for glutathione synthesis; also directly scavenges reactive oxygen species and modulates glutamate signaling. | Synthetic 29-amino-acid GHRH fragment that binds the GHRH receptor on pituitary somatotrophs to stimulate endogenous pulsatile GH synthesis and release while preserving the GH-IGF-1 negative feedback loop. |
| Legal status | OTC in most jurisdictions; restricted periods in US history (FDA reclassified 2022) | FDA approved 1997 (Geref, pediatric GHD); voluntarily discontinued by Serono 2008; compounded by 503A/503B pharmacies for off-label adult use; banned by WADA |
| WADA status | allowed | banned |
| DEA / Rx | OTC supplement (US, post-2022); Rx indications also exist (acetaminophen overdose, mucolytic) | Rx only via compounding (no controlled-substance schedule) |
| Pregnancy | Used clinically in pregnancy for specific indications; consult clinician | Category C (historical labeling); not recommended in pregnancy |
| CAS | 616-91-1 | 86168-78-7 |
| PubChem CID | 12035 | 16129617 |
| Wikidata | Q413299 | Q416620 |
Safety profile
N-Acetyl Cysteine
Common side effects
- sulfur-like taste or odor
- nausea
- flatulence
- diarrhea
Contraindications
- active asthma attack (inhaled form can trigger bronchospasm)
- known NAC hypersensitivity
Interactions
- nitroglycerin: potentiates vasodilation, risk of hypotension and headache(moderate)
- activated charcoal: reduces NAC absorption when used for acetaminophen overdose(moderate)
- anticoagulants: theoretical additive antiplatelet effect at high doses(minor)
Sermorelin
Common side effects
- injection-site pain or irritation
- transient flushing
- headache
- vivid dreams (pre-bed dosing)
Contraindications
- pregnancy
- active malignancy
- history of pituitary tumor
- diabetic retinopathy (theoretical)
- untreated hypothyroidism
Interactions
- ipamorelin: synergistic GH release via parallel GHRH and ghrelin pathways; standard anti-aging clinic pairing(minor)
- CJC-1295: pharmacologically redundant (both GHRH-pathway); typically not stacked(minor)
- insulin: sustained GH can blunt insulin sensitivity over weeks(moderate)
- corticosteroids: blunt GH response; reduce expected efficacy(moderate)
- levothyroxine (untreated hypothyroidism): untreated hypothyroidism blunts GH response; correct thyroid first(moderate)
Which Should You Take?
N-Acetyl Cysteine comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC, oral dosing, with a Tier-A outcome catalogued. Sermorelin is the right call when one of the conditionals below applies.
- → If your priority is liver function, pick N-Acetyl Cysteine.
- → If your priority is growth-hormone axis, pick Sermorelin.
- → If your priority is healthspan extension, pick N-Acetyl Cysteine.
Edge case: If you want to avoid FDA approved 1997 (Geref, pediatric GHD); voluntarily discontinued by Serono 2008; compounded by 503A/503B pharmacies for off-label adult use; banned by WADA, N-Acetyl Cysteine is the more accessible choice.
Default choice: N-Acetyl Cysteine. Wider use case, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Sermorelin only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between N-Acetyl Cysteine and Sermorelin?
N-Acetyl Cysteine and Sermorelin differ in category (supplement vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, N-Acetyl Cysteine or Sermorelin?
N-Acetyl Cysteine half-life is 5.6 hours; Sermorelin half-life is 0.25 hours.
Can you stack N-Acetyl Cysteine with Sermorelin?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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