HGH vs Sermorelin Dosing Comparison

HGH at 2 IU daily floods you with growth hormone right away. Sermorelin at 300 mcg nightly wakes up your pituitary to release it in natural pulses.

Go for HGH if you need reliable levels every time. I like Sermorelin better for mimicking your body's own rhythm. It's cheaper over time too.

Both build muscle and help with fat loss and recovery. The dosing, timing, and price are where they split. Here's how to run them.

HGH dosing protocols

Start low to see how you handle it. The doses below are anecdotal, community research-context figures that far exceed clinically endorsed growth hormone deficiency (GHD) replacement, which is only 0.2 to 0.6 mg/day (roughly 0.6 to 1.8 IU/day) (Yuen et al. 2019, Endocr Pract, PMID 31760818). No clinical guideline supports 2 to 6 IU/day. For fat loss or recovery, community users try 2 IU a day: 1 IU in the morning, 1 IU after your workout.

Mix a 10 IU vial (about 3.33 mg) into 1 ml bacteriostatic water. That makes 1 IU equal 0.1 ml on an insulin syringe. The math comes from the 3.0 IU/mg standard, which matches commercial 10 IU/3.33 mg somatropin vials (WHO 2nd International Standard for somatropin, 3.0 IU/mg, PMID 11580214).

• Fat loss stack: 2 to 3 IU every morning. Throw in 300 mcg AOD-9604 before bed. Track it with our HGH calculator and AOD-9604 calculator.
• Muscle growth: 4 to 6 IU a day, split as 2 IU AM, 2 IU post-workout, 2 IU evening. Run 5 days on, 2 off.
• Anti-aging: 1 to 2 IU right before bed.

To convert IU to mg, 1 mg usually equals 3 IU. So 4 IU comes to 1.33 mg. Weigh your empty and full vial to double-check.

Dose daily or split it up. The 2- to 3-hour half-life (Humatrope (somatropin) FDA label, PK section) means levels drop quick. A morning shot copies your natural peak, and an evening one helps overnight repair.

Sermorelin dosing protocols

Sermorelin triggers a GH pulse, so one dose at night does the trick. Community and clinic reports for compounded sermorelin land around 200 to 500 mcg, 30 minutes before bed on an empty stomach. Note there is no FDA-approved adult therapeutic dose: Geref was approved only for pediatric diagnosis/treatment and was discontinued in 2008, so these figures are community/clinic-reported rather than from controlled dose-finding trials.

Take a 5 mg vial and add 2.5 ml bacteriostatic water. Now 200 mcg is 0.1 ml.

• Beginner: 200 to 300 mcg every night. The IGF-1 response typically develops over weeks to months, though magnitude and timeline vary (community-reported).
• Advanced fat loss: 500 mcg nightly plus 200 mcg Ipamorelin. Check the Ipamorelin calculator.
• Recovery stack: 300 mcg Sermorelin plus 250 mcg CJC-1295. Our CJC-1295 / Ipamorelin calculator handles blends.

With a 10- to 20-minute half-life (Walker 2006, Clin Interv Aging, PMID 18046908), one injection sparks hours of GH. No reason to dose more.

Pair it with a GHRP like Ipamorelin. A GHRP combined with a GHRH releases GH synergistically (supraadditively) versus either alone (Bowers et al. 1990, J Clin Endocrinol Metab, PMID 2108187).

Half-life breakdown

HGH lasts 2 to 3 hours. It peaks quick and fades, so split doses to keep things even. Levels build to steady state after a few days.

Sermorelin clears in 10 to 20 minutes. It pokes your pituitary for a GH burst (which then lasts 2 to 3 hours, consistent with GH's terminal half-life) (Humatrope (somatropin) FDA label, PK section). Nightly shots line up with deep sleep pulses.

Sermorelin pulses GH the way your body did when you were younger. HGH just holds levels up constantly, more like straight replacement.

Administration step-by-step

HGH injection

1. Reconstitute 10 IU vial with 1 ml bac water. Gently roll it, don't shake.
2. Draw 10 units (1 IU) into U-100 insulin syringe.
3. Inject subQ into abdomen or thigh. Rotate sites.
4. Morning: Fast 20 minutes after. Evening: 2 hours post-meal.

Sermorelin injection

1. 5 mg vial + 2.5 ml bac water = 2 mg/ml.
2. Draw 10 units (200 mcg) U-100 syringe.
3. SubQ belly fat, 30 min pre-bed. No food 2 hours before/after.
4. Pin same time nightly for rhythm.

Both use 29-31G insulin syringes. Clean skin with alcohol. Store mixed at 2 to 8°C; the commonly cited 28-day window comes from the bacteriostatic-water/USP shelf-life convention rather than a peptide-specific stability study, and reconstituted somatropin product labels vary (for example, Humatrope's refrigerated dating) (Humatrope (somatropin) FDA label).

Frequency schedules head-to-head

Push HGH past 6 IU and you risk water retention. GH side effects like edema get worse with higher doses (Molitch et al. 2011, J Clin Endocrinol Metab, Endocrine Society AGHD guideline). Sermorelin reportedly causes less fluid retention than exogenous HGH, probably because the GH rise stays closer to physiologic levels (community/clinic-reported).

IU to mg conversions for HGH

Pharma HGH: 1 mg = 3 IU exactly (WHO International Standard for somatropin, 3.0 IU/mg, PMID 11580214; Genotropin USPI, 12 mg = 36 IU).

• 1 IU = 0.33 mg
• 2 IU = 0.67 mg
• 4 IU = 1.33 mg
• 6 IU = 2 mg

Pharmaceutical-grade rhGH is standardized at 3.0 IU/mg (WHO International Standard). Unverified gray-market product potency may vary, but that variability is community-reported and not a verifiable standard; values below 3 IU/mg would indicate impure or underpotent product. Test it: Dissolve a known amount of mg, check IGF-1 blood levels.

Plug your vial's IU/ml into the HGH calculator for exact ml per dose.

Sermorelin sticks to mg. 5 mg vials are standard.

Storage and stability

Unmixed powder:

• HGH: Room temp (under 25°C) 1 to 2 years. Fridge extends forever.
• Sermorelin: Room temp 2 years; fridge better.

Mixed in bac water:

• Both: 2 to 8°C. The 28-day figure follows the bacteriostatic-water/USP shelf-life convention rather than a sermorelin-specific stability study; reconstituted somatropin product labels vary (e.g., Humatrope's refrigerated dating). Discard if cloudy.
• Freezing OK for both. Thaw in the fridge once.

Travel: Unmixed powder fine. Mixed: Cooler bag 24 hours.

Keep both away from light and heat. Sermorelin's a touch less stable, so use it within 14 days of mixing if you're cautious.

Cost and longevity comparison

The prices below are approximate, variable market figures (illustrative, not a sourced fact). HGH 10 IU vial: $100-200, lasts 5 days at 2 IU/day.

Sermorelin 5 mg: $50-80, at 300 mcg/day = 16 days.

Monthly: HGH $600-1200 (2 IU/day); Sermorelin $100-200.

Sermorelin is the cheaper option. HGH hits harder and faster if you can afford it.

Stacking options

Sermorelin stacks (GH release peptides):

• Sermorelin 300 mcg + Ipamorelin 200 mcg: produces a synergistic GH pulse greater than either peptide alone (Bowers et al. 1990, J Clin Endocrinol Metab, PMID 2108187). Ipamorelin
• • CJC-1295 100 mcg to make the pulse last longer. CJC-1295 / Ipamorelin
• Add TB-500 2.5 mg 2x/week for repair. TB-500

HGH stacks:

• HGH 2 IU + BPC-157 250 mcg 2x/day for gut and joint healing. BPC-157
• • AOD-9604 300 mcg AM for fat burning. AOD-9604
• Advanced: HGH 4 IU + low Sermorelin 100 mcg for hybrid.

GHK-Cu 1 mg daily pairs with both for skin/collagen.

Protocols for specific goals

Fat loss protocol

• HGH route: 2 IU AM fasted, 2 IU PM. Cardio 30 min post-AM dose. 12 weeks.
• Sermorelin route: 400 mcg + 200 mcg Ipamorelin nightly. Deficit diet. 3 months buildup.

Anecdotal community reports cite 1-2 pounds fat/week on HGH and 0.5-1 on Sermorelin, but no clinical trial supports these specific rates. GH fat-mass effects are modest and depend on dose and duration, not a fixed 1-2 lb/week.

Muscle building

• HGH: 4 IU split + heavy lifts 4x/week.
• Sermorelin: 500 mcg nightly + test base if allowed. Slower gains.

Injury recovery

• HGH 2 IU nightly + TB-500.
• Sermorelin 300 mcg + BPC-157 500 mcg/day.

IGF-1 blood test at 4 weeks: IGF-1 should be kept within the age- and sex-adjusted normal reference range rather than to a single universal number (Molitch et al. 2011, J Clin Endocrinol Metab, Endocrine Society AGHD guideline).

Sides and management

HGH: numb hands from carpal tunnel mean you should lower the dose, and water weight usually responds to cutting sodium. These effects get worse with higher doses. Edema, joint pain, and paresthesia show up in roughly 5-18% of treated adults with GHD, and carpal tunnel in about 2% (Molitch et al. 2011, J Clin Endocrinol Metab, Endocrine Society AGHD guideline).

Sermorelin: occasional flushing or headache, usually sorted by dosing on an empty stomach.

Both raise IGF-1, so monitor glucose yearly.

Cycling HGH 3-6 months and running Sermorelin indefinitely is a community protocol convention, not clinical guidance (GHD is dosed continuously to an IGF-1 target).

Sermorelin vs HGH: when to choose each

• Pick HGH if budget allows or you want fast results; some community users also favor it past age 40 on the assumption of a slower pituitary, though that framing is an oversimplification and not clinical guidance.
• Pick Sermorelin for natural pulse, low cost, no shutdown risk.

A lot of people run Sermorelin for years and add HGH blasts on top.

Track with Sermorelin calculator.

This is for educational purposes only. Consult a healthcare professional before using any peptides. Dosingcalc.com provides tools for research calculations, not medical advice.

References

1. Eli Lilly. "Humatrope (somatropin) Prescribing Information." FDA label
2. Walker RF. "Sermorelin: a better approach to management of adult-onset growth hormone insufficiency?" Clin Interv Aging, 2006. PubMed
3. Bowers CY, Reynolds GA, Durham D, et al. "Growth hormone (GH)-releasing peptide stimulates GH release in normal men and acts synergistically with GH-releasing hormone." J Clin Endocrinol Metab, 1990. PubMed
4. World Health Organization. "WHO International Standard for somatropin (3.0 IU/mg)." PubMed
5. Pfizer. "Genotropin (somatropin) Prescribing Information (12 mg = 36 IU)." Pfizer labeling
6. Molitch ME, Clemmons DR, Malozowski S, et al. "Evaluation and Treatment of Adult Growth Hormone Deficiency: An Endocrine Society Clinical Practice Guideline." J Clin Endocrinol Metab, 2011. Journal
7. Yuen KCJ, Biller BMK, Radovick S, et al. "American Association of Clinical Endocrinologists and American College of Endocrinology Guidelines for Management of Growth Hormone Deficiency in Adults and Patients Transitioning from Pediatric to Adult Care." Endocr Pract, 2019. PubMed