Sermorelin Side Effects: What Is Documented, When to Stop, and What Is Not Known

Everything below is research use information. It is not medical advice, it is not a recommendation to start or stop anything, and none of it substitutes for supervision by a qualified clinician who can see your bloodwork and your history. Every figure on this page links to the primary source it came from, listed at the bottom.

Sermorelin Side Effects at a Glance: How Often Each One Was Recorded

The table below is built only from documents that report a number: the US prescribing information for Geref, the FDA's own summary of the Geref safety record, the European label for the single-dose diagnostic version, and the small adult trials. Where a row says "not recorded", the Bureau looked and found no rate.

The Geref rates come from children with growth hormone deficiency on about 30 micrograms per kilogram a day, a different population and purpose from adults using sermorelin as a research compound. The rates are the best controlled record that exists, not a prediction for any one person.

Where the Evidence Comes From

Sermorelin is the first 29 amino acids of growth hormone releasing hormone. The FDA approved it twice under the name Geref: as a single-dose diagnostic test in December 1990 and as a daily treatment for children with idiopathic growth hormone deficiency in September 1997. The maker stopped selling both in 2008, the FDA withdrew the approvals effective 18 June 2009, and in March 2013 the agency formally determined that both Geref products "were not withdrawn for reasons of safety or effectiveness".³ No official document gives the commercial reason. That determination matters because it is the only regulatory statement on sermorelin's safety, and it is a neutral one.

The adult record is thin. Three small trials did the work: 10 men aged about 68 for 14 days (Corpas 1992), 11 men aged 64 to 76 on 2 mg nightly for 6 weeks (Vittone 1997), and 9 men and 10 women aged 55 to 71 on a close analogue for 16 weeks (Khorram 1997).^8,6,7 None reported a serious adverse effect: Corpas found no change in glucose, blood pressure or blood chemistry, Vittone recorded "no significant adverse effects", and Khorram's only finding was a temporary rise in blood lipids. Thirty-nine adults across three short trials is the core of the controlled adult record the Bureau could find, and it is far too small to see anything uncommon.

Why the profile looks milder than injected growth hormone: sermorelin asks the pituitary to release its own hormone rather than adding hormone directly, so somatostatin, the body's brake, stays in the loop. In the 110-child trial there was "no change in fasting glucose concentration or excessive generation of insulin-like growth factor I".⁵ That is reassuring, but it is not a guarantee that a releasing hormone cannot overshoot: tesamorelin, a related and more stable analogue, pushed IGF-1 above 2 standard deviations in 47.4 percent of patients at 26 weeks and above 3 in 35.6 percent.⁹ The number worth trusting is a measured IGF-1, not the mechanism. The ipamorelin versus sermorelin comparison covers how the two differ in the pulse they produce.

Injection Site Reactions

This is the one to expect: about 1 patient in 6 in the Geref trials had pain, redness or swelling where the needle went in, and 3 of 350 stopped because of it.² Some of that is the injection itself rather than the compound; for comparison, 14.4 percent of people injecting placebo in the tesamorelin trials had an injection site reaction too.⁹

Most of the practical levers are technique. Rotating sites, letting the alcohol dry fully, allowing cold material to warm first, using a fresh rather than a blunted needle, and keeping the injected volume small all reduce local irritation. The injection guide covers rotation and technique, and the sermorelin dosage calculator shows what volume a given vial strength and water volume produce, the variable people forget is adjustable. A reaction that spreads, blisters, hardens into a lasting lump, or arrives with fever is not ordinary irritation and is a reason to see a clinician.

Flushing, Headache and Dizziness

These are the effects people online describe most after injection site reactions, but the controlled record puts each of them under 1 percent in the paediatric trials.¹ With the single intravenous diagnostic dose, facial heat and flushing "occasionally occur and usually disappear within a few minutes".⁴ That timing fits the pharmacology: sermorelin has a plasma half-life of 6 to 7 minutes after an intravenous dose, and the growth hormone peak it triggers arrives about 30 minutes later.⁴

So a flush in the minutes after a dose is a recognised, short-lived effect. A headache that persists, or arrives with any change in vision, is not part of that picture and is a reason to stop and get seen. Headache is common enough in daily life that attributing a single one to sermorelin without a control arm is guesswork.

Water Retention and Joint Aches

This is where online lists and the evidence part company. Puffy hands, joint fullness and finger tingling are classic effects of raised growth hormone, and they are on the label for tesamorelin, where arthralgia was reported by 13.3 percent against 11.0 percent on placebo and peripheral oedema by 6.1 percent against 2.3 percent.⁹ But no sermorelin source the Bureau found lists them, and in both multi-week adult trials body weight and blood pressure did not change.^6,7

The fair reading: fluid effects are plausible with any compound that raises growth hormone, more so the higher the IGF-1 response, but for sermorelin they are inferred from related drugs rather than measured. If they appear and do not settle within a couple of weeks, the response is to lower the dose or stop, and to check IGF-1. The before and after timeline covers what shows up in which week and what is noise.

What Happens to Sleep

Sermorelin is usually dosed at bedtime because the largest natural growth hormone pulse comes with the onset of deep sleep: in men it is generally the main daily secretory episode, and maximal release occurs within minutes of stage 3 or 4 sleep starting.^12,13 Users often report deeper sleep, grogginess on waking or vivid dreams. The one adult trial that measured it found sleep quality "unaffected in both genders" over 16 weeks.⁷ Treat sleep changes, good or bad, as anecdote; if a bedtime dose leaves you heavy in the morning, moving it earlier in the evening is the usual adjustment.

When Each Effect Shows Up: A Timeline From the Trials

Each row below is tied to a measured timepoint. Where a study measured nothing at a given point, the row says so.

Two things are worth taking from it. The early effects are local and short-lived. And the one adult trial long enough to look found the IGF-1 effect fading by week 16, which is one more reason to judge a block by a blood result rather than by the calendar.

Cortisol, Prolactin and Glucose

Cortisol and prolactin. This worry is borrowed from the ghrelin-mimetic secretagogues such as GHRP-6 and ipamorelin, which act at a different receptor. Sermorelin acts at the growth hormone releasing hormone receptor, and none of the sermorelin trials cited here reported a cortisol or prolactin problem. The concern has been transferred by association rather than by evidence.

Glucose. Growth hormone opposes insulin, so the question is fair. The sermorelin record is clean: no change in fasting glucose in the 110-child trial, nor in the three adult trials.^5,8,6,7 Tesamorelin is the warning from the same family: in its 26-week trials 4.5 percent of treated patients reached an HbA1c of 6.5 percent or more against 1.3 percent on placebo, and its label asks for glucose monitoring.⁹ Anyone with existing glucose problems has a real reason to be supervised rather than to guess.

Glucose also works in the other direction: it blunts the response. In a small study, a 75 g glucose drink 30 minutes before a dose of growth hormone releasing hormone cut the growth hormone peak from 23.7 to 8.1 ng/mL.¹¹ The European label notes that obesity and high blood sugar are generally associated with poor responses.⁴ That is the evidence behind the advice to dose away from food; the sermorelin dosage guide covers the timing.

What Not to Take With Sermorelin

The US label for the treatment product names one interaction: glucocorticoids (such as prednisone) may inhibit the response.² The European label for the diagnostic test lists more, because a test result is easy to distort: anything containing or releasing somatostatin, insulin or glucocorticoids, and cyclooxygenase inhibitors such as aspirin and indomethacin, should be avoided; clonidine, levodopa and insulin-induced low blood sugar can transiently raise growth hormone; atropine-type anticholinergics can reduce the response; and beta blockers and beta agonists may affect it.⁴ Those were written for a single diagnostic dose, but they are the documented list. Combining sermorelin with injected growth hormone or other compounds that raise IGF-1 stacks the same pathway, and anyone on thyroid medication, insulin or steroids needs the combination supervised.

The Long Term Question, Stated Plainly

There is no multi-year controlled follow-up of adults using sermorelin for body composition, sleep or general wellbeing. The longest human exposure is paediatric: a one-year trial of 110 children, with data on a few children out to 36 months.^5,14 That is a different population with a different purpose, and it cannot be stretched over adult use. So the accurate statement is that long term sermorelin side effects are unknown, not that they are absent. Anyone presenting a confident long term safety claim in either direction is filling a gap rather than reporting a finding.

Who Should Not Use It, and Why Supervision Matters

Some categories are not close calls. The European label says the product should not be used during pregnancy or breastfeeding.⁴ An active or recent malignancy is the clearest mechanistic exclusion, because IGF-1 is a growth signal. Thyroid disease matters because hypothyroidism appeared during treatment in 6.5 percent of the Geref children and the label asked for thyroid tests before and during therapy.² Anyone on glucocorticoids, insulin or other endocrine medication, and anyone under eighteen, belongs in a clinician's office rather than a forum thread.

There is also a risk that has nothing to do with the molecule. Sermorelin sold as a research chemical carries no assurance of identity, purity or sterility, and a contaminated or mislabelled vial produces problems no careful dosing prevents. The peptide testing guide explains what a certificate of analysis can and cannot prove, and the general peptide side effects page makes the case that supply quality is often the larger variable.

When to Stop, and How to Stop

No sermorelin study describes a withdrawal syndrome, and in the 16-week adult trial the IGF-1 rise was already fading while people were still dosing.⁷ In healthy men given tesamorelin, a related analogue, IGF-1 was no longer significantly different from baseline two weeks after stopping.¹⁵ What matters is recognising the signals that mean stop now rather than stop at the end of the block.

Stop and get seen for an injection site reaction that spreads beyond the site, blisters, hardens into a lasting lump or comes with fever; for hives, facial or lip swelling, or any trouble breathing after a dose, which is an allergic reaction rather than a side effect; for a severe or persistent headache, especially with any change in vision; and for new chest symptoms or palpitations.

Stop or reduce, and review with a clinician when hand or finger tingling, swelling or joint pain persists beyond a couple of weeks rather than settling; when fasting glucose or HbA1c has moved on repeat testing; when IGF-1 sits above the reference range for age on a second measurement; when thyroid tests change; and on any new diagnosis of a malignancy, or pregnancy, where the compound has no place at all.

Planned stops are a different matter. The sensible reassessment points are the ones with a number to look at: IGF-1 and fasting glucose after eight to twelve weeks. If the first block produced nothing measurable at a sensible dose, that is itself information, and the answer is rarely a higher dose. The peptide cycles guide covers why secretagogues are usually run in blocks.

Sermorelin Side Effects in Women

The only controlled data come from Khorram 1997, which included 10 women aged 55 to 71 for 16 weeks. Growth hormone and IGF-1 rose in both sexes and no adverse effects were seen beyond the temporary lipid rise, but the benefits split by sex: lean mass, insulin sensitivity, general wellbeing and libido improved in the men only, while growth hormone binding protein rose in the women only.⁷ Sermorelin has no activity at androgen or oestrogen receptors, and the hair, voice and skin changes associated with androgenic compounds are not part of its record.

Three things differ in practice. First, oral oestrogen blunts the IGF-1 step: in postmenopausal women, oral ethinyl oestradiol lowered IGF-1 from 0.70 to 0.47 U/mL while a transdermal patch raised it.¹⁰ Applying that to the contraceptive pill is an inference, but it is a reason the number to watch is the IGF-1 result, not the dose. Second, women's growth hormone rhythm is different, with frequent daytime pulses rather than one dominant night pulse,¹² so the bedtime-dosing logic is weaker. Third, the cyclical fluid shifts many women notice make any puffiness harder to read; the morning weight trend tells you more than a single day. Pregnancy and breastfeeding are a stop, full stop.⁴

Dose, Titration and What to Monitor

The paediatric dose was about 30 micrograms per kilogram once daily at bedtime.⁵ Adult research protocols vary widely; the sermorelin dosage guide covers them and where they come from. Local reactions appear at any dose, while the growth hormone effects (fluid, joints, glucose) would be expected to rise with the IGF-1 response, which is why titration, starting low and moving only if nothing measurable happens, is the tool that works.

Worth having measured, with a clinician reading the results: IGF-1 at baseline and again after a couple of months, fasting glucose and HbA1c, and thyroid function, which the Geref label asked for before and during treatment.² Worth recording yourself: injection sites and reactions, morning weight, ring or shoe fit as a crude fluid proxy, sleep quality, and any joint symptoms with dates.

Frequently Asked Questions

How common are sermorelin side effects?

In the trials behind the approved product, about 1 patient in 6 had an injection site reaction and 3 of 350 stopped because of it. Every other treatment-related effect, including flushing, headache, dizziness, drowsiness, hyperactivity, trouble swallowing and hives, occurred in under 1 percent. Hypothyroidism appeared in 6.5 percent during therapy. Those rates come from children treated for growth hormone deficiency, so they are a guide rather than a prediction for adults.

Was sermorelin taken off the market for safety reasons?

No. Geref was discontinued in 2008 and its approvals were withdrawn in 2009, and in March 2013 the FDA published a formal determination that it was not withdrawn for reasons of safety or effectiveness. No official document states the commercial reason.

What does sermorelin do to your face?

The documented effect is facial flushing or heat, recorded in under 1 percent in the paediatric trials and described as occasional and gone within minutes after a diagnostic dose. Facial puffiness is reported by users and is plausible as a growth hormone effect, but no sermorelin trial recorded it. The coarsening of features linked to long term growth hormone excess has not been reported with sermorelin, though no long term adult study exists to close the question.

What should you not take with sermorelin?

The US label names glucocorticoids, which may inhibit the response. The European diagnostic label adds somatostatin and insulin-containing preparations, aspirin and indomethacin type cyclooxygenase inhibitors, and atropine type anticholinergics, which can reduce the response, plus clonidine and levodopa, which can transiently raise growth hormone, and possibly beta blockers and beta agonists. Glucose before a dose also blunts it: a glucose drink 30 minutes beforehand cut the growth hormone peak by about two thirds in one study.

How long can you stay on sermorelin?

There is no studied maximum for adults. The main paediatric trial ran a year and a few children continued to 36 months; the longest adult trial ran 16 weeks, and in it the IGF-1 rise was fading by the end. The practical answer is to stay on it only as long as a measured result justifies it, with IGF-1, fasting glucose, HbA1c and thyroid function checked at the start and every few months, and to stop at any of the signals listed above.

Does sermorelin cause cancer?

No study links sermorelin to new cancers, and no study has been designed that could detect it, so the honest answer is unknown rather than no. The concern is mechanistic: IGF-1 is a growth signal, and raising it deliberately in someone with an active or recent malignancy is a decision no one should make informally. Anyone with a personal or strong family cancer history belongs with a clinician, not a protocol.

Is sermorelin safe?

Safe is the wrong word for a compound with this evidence base. Sermorelin was approved and marketed as a prescription medicine, the effects recorded in that record were mostly local and mostly mild, and the FDA has said it was not withdrawn for safety reasons. What cannot be said is that it is safe for any particular person, which depends on the individual, on monitoring, and on a supply chain that research grade material does not guarantee.

What are the long term side effects of sermorelin?

Unknown. The longest human exposure is a one-year paediatric trial with a few children followed to 36 months. For adults using it for body composition, sleep or wellbeing there is no multi-year controlled follow-up, so long term effects are unknown rather than absent.

How do you reduce a sermorelin injection site reaction?

Injection site reactions are the most common recorded effect, about 1 in 6 in the licensed product's trials, and most of the levers are technique rather than dose. Rotating sites, letting the alcohol dry before the needle goes in, letting cold material warm first, using a fresh needle each time, and reconstituting so the injected volume is small all help. A reaction that spreads, blisters, hardens or comes with fever warrants medical attention.

Does sermorelin cause water retention?

It is plausible but not documented for sermorelin itself. Fluid retention, joint pain and carpal tunnel symptoms are on the label of tesamorelin, a related growth hormone releasing hormone analogue, but no sermorelin source lists them, and body weight and blood pressure did not change in the adult sermorelin trials. If puffiness or joint aches appear and do not settle, lower the dose or stop, and check IGF-1.

Are sermorelin side effects different in males?

The recorded side effects do not differ by sex. In the one trial that included both, growth hormone and IGF-1 rose in men and women alike and no adverse effects were seen beyond a temporary lipid rise; the benefits differed, with lean mass, insulin sensitivity, wellbeing and libido improving in men only. Sermorelin does not act on androgen pathways.

Is sermorelin on the FDA's restricted compounding list?

No. As of the FDA's 22 April 2026 update, sermorelin is not on the list of bulk drug substances the agency says may present significant safety risks in compounding (Category 2), where ipamorelin, GHRP-2 and GHRP-6 sit for outsourcing facilities.¹⁶ That is not the same as the FDA saying it may be compounded; the legal status guide explains the categories.

Sources

1. US Food and Drug Administration. Medical review of EGRIFTA (tesamorelin), NDA 22-505, section 2.4, summarising the Geref (sermorelin) safety record. 2010. accessdata.fda.gov
2. Geref (sermorelin acetate) prescribing information, FDA revision 2 October 2001, as reproduced by RxList (the FDA does not host the original). rxlist.com
3. Federal Register. Determination that GEREF (sermorelin acetate) injection was not withdrawn from sale for reasons of safety or effectiveness. 78 FR 14095, 4 March 2013, docket FDA-2012-P-1071. govinfo.gov
4. Geref 50 micrograms (sermorelin), summary of product characteristics, Health Products Regulatory Authority, Ireland. hpra.ie
5. Thorner M, et al. Once daily subcutaneous growth hormone-releasing hormone therapy accelerates growth in growth hormone-deficient children during the first year of therapy. J Clin Endocrinol Metab. 1996. PubMed 8772599
6. Vittone J, et al. Effects of single nightly injections of growth hormone-releasing hormone (GHRH 1-29) in healthy elderly men. Metabolism. 1997. PubMed 9005976
7. Khorram O, et al. Endocrine and metabolic effects of long-term administration of [Nle27]growth hormone-releasing hormone-(1-29)-NH2 in age-advanced men and women. J Clin Endocrinol Metab. 1997. PubMed 9141536
8. Corpas E, et al. Growth hormone (GH)-releasing hormone-(1-29) twice daily reverses the decreased GH and insulin-like growth factor-I levels in old men. J Clin Endocrinol Metab. 1992. PubMed 1379256
9. EGRIFTA (tesamorelin for injection) prescribing information, 2010. accessdata.fda.gov
10. Weissberger AJ, et al. Contrasting effects of oral and transdermal routes of estrogen replacement therapy on 24-hour growth hormone secretion, insulin-like growth factor I, and GH-binding protein in postmenopausal women. J Clin Endocrinol Metab. 1991. PubMed 1991807
11. Masuda A, et al. The effect of glucose on growth hormone (GH)-releasing hormone-mediated GH secretion in man. J Clin Endocrinol Metab. 1985. PubMed 3919046
12. Van Cauter E, Plat L. Interrelationships between growth hormone and sleep. Growth Horm IGF Res. 2000. PubMed 10984255
13. Holl RW, et al. Thirty-second sampling of plasma growth hormone in man: correlation with sleep stages. J Clin Endocrinol Metab. 1991. PubMed 2005213
14. Prakash A, Goa KL. Sermorelin: a review of its use in the diagnosis and treatment of children with idiopathic growth hormone deficiency. BioDrugs. 1999. PubMed 18031173
15. Stanley TL, et al. Effects of a growth hormone-releasing hormone analog on endogenous GH pulsatility and insulin sensitivity in healthy men. J Clin Endocrinol Metab. 2011. PMC3038486
16. US Food and Drug Administration. Certain bulk drug substances for use in compounding that may present significant safety risks (updated 22 April 2026). fda.gov

Every figure above was checked against the linked source on 4 October 2026. Spotted something out of date? Email bureau@peptidebureau.com with the link and the page will be corrected and dated.