Page last checked 2026-08-12

Growth hormone C-terminal fragment (research compound) · safety

AOD-9604 side effects

Also written AOD 9604.

The aod-9604 side effects reported most often are mild, transient headache, fatigue and injection reactions. The full list is below, with the cited trial report cited at the bottom of the page.

Rarer, but worth being able to spot: unknown long-term risk.

The sources describe these effects in relation to the dose and to the early weeks.

AOD-9604 is the tail end of human growth hormone — residues 176 to 191, with one extra amino acid added on the front. It is sold for fat loss, on the idea that this fragment carries the hormone’s fat-mobilizing part and leaves the rest behind.

That idea was tested properly and it did not hold. An Australian company ran controlled human obesity trials, the larger ones did not separate it from placebo on weight, and development stopped there. The 10 mg group lost less than the 1 mg group, and the doses were swallowed rather than injected.

Further down: the full list with frequencies · when to get medical help · questions

Medically reviewed by Jennifer Montecillo, MD · non-practicing medical reviewerReviewed 2026-08-12open the primary sources

At a glance

Common reactions listed

Serious reactions listed

Boxed warning

No label exists

Strongest source

limited human data

The counts show how many distinct reactions the cited trial report names. The percentages show how often a reaction appeared in a study group, not the chance that it will happen to you.

Common reactions

The full list, as reported across the available trial evidence. There is no approved label to read frequency bands off, so these are the trials’ own figures.

◆ Common reactionstrial-reported

Reaction	Frequency
Mild, transient headache	Reported in human safety work that reaches this page only through a review — no rate is published
Fatigue	Reported in human safety work that reaches this page only through a review — no rate is published
Injection reactions	Reported in human safety work that reaches this page only through a review — no rate is published
No significant change in glucose tolerance or IGF-1	The stated finding of the human work — the fragment did not move the glucose and IGF-1 measures that whole growth hormone does

Serious reactions to watch for

These are rarer, and they are the ones clinicians monitor for. Seek medical care if you have symptoms.

◆ Serious — monitorwarning/precaution

Reaction	Frequency
Unknown long-term risk	No long-term safety data exists, and the trials that would have generated it were stopped for lack of effect and never published — monitor

limited human dataEvery reaction above comes from a cited trial. These are study findings, not instructions on what to take.

When to seek medical care

The trial report does not give a separate list of serious reactions. There is also no approved label. That gap does not mean serious reactions cannot happen. This compound has been studied in fewer people and for less time than an approved drug.

EmergencySome symptoms should not wait for an appointment. Call emergency services (911 in the US) if they are severe, getting worse fast, or involve trouble breathing, chest pain, fainting or confusion.

1Read deeperTiming, evidence limits, and product context

When these effects tend to occur

The cited evidence describes these effects in relation to the dose and to the early period of taking it, rather than as a constant background throughout.

When a study reports how side effects changed over time, it describes the group as a whole. It cannot predict one person’s experience.

Common questions

How long do aod-9604 side effects last, and do they go away?

The sources do not commit to a set number of days. What they describe is a pattern — reactions cluster after you start and after each increase, then ease while the dose is held steady. Any page quoting an exact number of days is quoting something the sources do not say.

What are the most common aod-9604 side effects?

Mild, transient headache, fatigue, injection reactions and no significant change in glucose tolerance or IGF-1 — the table above has the rest, each with its frequency band and source.

Does aod-9604 have a boxed warning?

No, because a boxed warning is part of an FDA-approved label and aod-9604 has no approved label. That reflects what regulatory review has and has not covered, not a finding that serious risks were looked for and ruled out.

Can the aod-9604 dose be lowered if side effects are hard to tolerate?

That decision belongs to the prescribing clinician. No approved schedule exists for this compound, so there is no labeled framework for adjusting a dose. That leaves the prescriber as the only place the decision can sit.

Does aod-9604 cause hair loss?

Hair loss is not among the reactions listed on this page for aod-9604, because the cited trial report cited here does not carry it. Anything missing from the tables is outside what can be sourced here rather than ruled out, and a symptom that worries you belongs with a clinician.

Is fatigue a listed aod-9604 side effect?

Yes — it is in the common reactions table above, with its frequency band. Being listed means it came up often enough in the trial population to reach the cited trial report; it does not establish the cause in any one case.

Is constipation a listed aod-9604 side effect?

Not separately. If a source groups stomach and gut events together, this page keeps that group intact. It does not invent named reactions the source never listed.

What should someone do about a serious aod-9604 reaction?

Contact a clinician promptly, and emergency services if symptoms are severe or getting worse quickly. The section above describes what those reactions actually look like, so they can be spotted early rather than explained away.

Do the frequencies on this page mean the chance it happens to one person?

No. These figures describe groups in a study. A band shows how often a reaction appeared under that trial’s conditions. It cannot predict what will happen to one person.

The schedule these reactions were recorded against, the comparisons, and the sourcing rules behind every grade on this page.

How strong the evidence is for AOD-9604

The strongest source for AOD-9604 is a foreign approval or thin human data.

How the AOD-9604 trials escalated to their top arm

The strongest dose source for AOD-9604 is a foreign approval or thin human data.

Doses per 5 mg AOD-9604 vial, on the calculator

The nearest syringe line to the target, and the rounding error it introduces for AOD-9604.

Every calculator on this site, AOD-9604 and the rest

Every intermediate value is printed, for AOD-9604 or any other vial.

Fatigue weighed class-wide, including AOD-9604

Named fatigue entries, grouped figures and absences kept distinct, apart from AOD-9604.

Every compound guide, AOD-9604 and the rest

Class, approval status and strongest available source for every compound, with AOD-9604 as one example

AOD-9604 in the regulatory changelog

A proceeding with no published outcome is entered as exactly that, including AOD-9604

Why these AOD-9604 sources were chosen

How an FDA label differs from a human trial or a claim with no human data, with AOD-9604 as one example

Questions readers ask

How long does it take for an AOD-9604 to work?

The trials ran 12 and 24 weeks, and none of them timed an onset. In the 12-week trial the 1 mg group lost 2.6 kg against 0.8 kg on placebo.

The 24-week trial in 536 participants ended the development program in 2007. Neither trial has a primary paper, so the available figures come from a review of a company announcement.

Is AOD-9604 safe?

Every safety line here is second-hand, which makes it the weakest record in this registry. A human safety paper exists, but no host this site treats as primary carries it.

What reaches the page is a 2026 review’s summary. It lists mild passing headache, fatigue and sore injection sites, with no incidence figures. The same review reports no change in glucose handling or IGF-1.

How much weight can you lose on aOD?

The best published figure is 2.6 kg over 12 weeks, in the 1 mg group, against 0.8 kg on placebo. More did not do more: the 10 mg group lost less than the 1 mg group.

The larger 24-week trial did not separate the compound from placebo at all. Those trials swallowed it rather than injecting it, and at roughly ten times what circulates today.

Can AOD-9604 help with weight loss?

Controlled human obesity trials failed to separate it from placebo on weight, and development stopped there. This fragment is not unstudied — it is unsuccessful, which is a stronger finding than an absence of evidence.

It later found a second life as a food and supplement ingredient, and anti-doping authorities decided against prohibiting it. A substance can be legal, on sale and useless at once.

1primary source, each with the day we read it — open the documents used on this page

Dominikowski A, Rękoś Z, Olejarz M, Szczepanek-Parulska E, Domin R, Ruchała M. The emerging landscape of performance-enhancing peptides modulating GH-IGF1 axis: bridging the gap between clinical evidence and patient self-administration. Front Endocrinol 2026;17 — Table 1, AOD9604 safety-signal row, sourced there to Stier 2013retrieved 2026-08-12limited human data