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Melanotan II vs Ipamorelin side-by-side

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Melanotan IIIpamorelin

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Property	Melanotan II	Ipamorelin
Category	Sexual Health	Growth Hormone
Also known as	MT-II, MT2, Melanotan 2	IPAM, NNC 26-0161
FDA approved	No	No
Clinical status	Not approved; research reportedly discontinued due to side effects. Source also lists FDA Category 2 restricted status tied to melanoma risk and other safety concerns. Pre Preclinical I Phase I II Phase II III Phase III IV Phase IV FDA FDA approved	Investigational; Phase II trials discontinued. Listed as FDA Category 2 pending possible reclassification, with formal status not changed in the source. Pre Preclinical I Phase I II Phase II III Phase III IV Phase IV FDA FDA approved
What to expect	Tanning, libido enhancement, erectile function	Anti-aging, muscle building, sleep quality, recovery
How it works	Melanotan II is reported as a broad melanocortin receptor agonist rather than a receptor-selective compound. The source names MC1, MC3, MC4, and MC5 as targets. MC1 signaling in melanocytes is tied to melanin production, while MC4 signaling in the central nervous system is linked to sexual arousal and desire pathways. The broad receptor profile is also presented as a reason for a wider adverse-effect profile.	Ipamorelin is reported to activate GHS-R1a, the ghrelin or growth hormone secretagogue receptor, on somatotroph cells in the anterior pituitary. The source links this receptor activity to Gq/phospholipase C signaling, IP3 generation, intracellular calcium release, and pulsatile release of stored growth hormone. It also describes ipamorelin as relatively selective in early characterization, with GH-releasing doses not meaningfully increasing ACTH, cortisol, prolactin, FSH, LH, or TSH. Because the mechanism relies on pituitary GH stores, the source indicates that pituitary function and normal feedback biology remain relevant to the response.
Typical dosing	250-500 mcg daily (loading), then 500-1,000 mcg weekly (maintenance) · Daily during loading (1-2 weeks), then weekly maintenance · Loading 1-2 weeks, then maintenance · Subcutaneous injection	200-300 mcg 2-3x daily · 2-3x daily
Research dosing	250-500 mcg initially · Loading phase 2-3 weeks, then maintenance · Subcutaneous injection	100-300 mcg per injection · 8-12 weeks typical · Subcutaneous injection
Typical duration	Loading phase 2-3 weeks, then maintenance	8-12 weeks typical
Administration	Subcutaneous injection	Subcutaneous injection
Timing	Evening or before sun exposure With or without food	Before bed or morning, fasted Fasted timing reported
Evidence level	Research	Clinical Trials
Possible side effects	Nausea (Reported as common, especially initially.) Facial flushing Fatigue +6 more Spontaneous penile erections Darkening of skin and moles (Source highlights mole changes and pigmentation concerns.) Priapism (Source flags this as an emergency-risk adverse event.) Association with melanoma risk (Source links restricted status and dermatology cautions to melanoma risk concerns.) Possible histamine release (Source advises caution for MCAS or histamine sensitivity.) Legal restriction caution (Source reports illegality in the US, UK, and Australia; this regulatory claim needs admin review.)	Generally well tolerated (Reported by the source as a general tolerability statement, not a guarantee of safety.) Injection-site reactions Headache +6 more Nausea Increased appetite Water retention Temporary joint stiffness (Source describes joint stiffness as temporary.) No significant cortisol or prolactin elevation reported (Source presents this as a selectivity-related observation.) Contraindicated with active malignancy (Listed by the source as a contraindication.)
Research summary	The supplied research summary describes narrow older human evidence for erectile-function outcomes. In men with organic erectile dysfunction, the source reports subjectively described erections after 12 of 19 Melanotan II injections compared with 1 of 21 placebo doses, plus longer rigidity periods and greater sexual interest; nausea and yawning were frequent. The source connects this effect profile to later bremelanotide development. For tanning, the same source emphasizes lack of large safety trials and dermatology concerns including changing moles, melanoma reports, uneven or lasting pigmentation changes, nausea, and risks from unregulated injected material.	The source identifies Raun et al. 1998 as early foundational work and describes characterization across rats, pigs, and isolated pituitary cells. It reports that ipamorelin released GH without corresponding ACTH or cortisol increases at doses above the GH-release threshold. The source also notes that human development reached Phase II for postoperative ileus before being discontinued for insufficient efficacy. For popular wellness uses such as anti-aging, fat loss, muscle gain, or recovery, the source states that large peer-reviewed human randomized trials are not available and that these claims are extrapolated from mechanism rather than established outcomes.
References	WikipediaMelanotan II PubMedPubMed record 11018622 +1 more DermNetMelanotan II	PubMed PubMed +1 more PubMed
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Educational use only. This information is aggregated from public research and community reports. It is not medical advice, and dosing details are descriptive, not recommendations. Always consult a qualified healthcare professional.

Property

Melanotan II

Ipamorelin

Category

Sexual Health

Growth Hormone

Also known as

MT-II, MT2, Melanotan 2

IPAM, NNC 26-0161

FDA approved

Clinical status

Not approved; research reportedly discontinued due to side effects. Source also lists FDA Category 2 restricted status tied to melanoma risk and other safety concerns.

Pre
Preclinical
I
Phase I
II
Phase II
III
Phase III
IV
Phase IV
FDA
FDA approved

Investigational; Phase II trials discontinued. Listed as FDA Category 2 pending possible reclassification, with formal status not changed in the source.

Pre
Preclinical
I
Phase I
II
Phase II
III
Phase III
IV
Phase IV
FDA
FDA approved

What to expect

Tanning, libido enhancement, erectile function

Anti-aging, muscle building, sleep quality, recovery

How it works

Melanotan II is reported as a broad melanocortin receptor agonist rather than a receptor-selective compound. The source names MC1, MC3, MC4, and MC5 as targets. MC1 signaling in melanocytes is tied to melanin production, while MC4 signaling in the central nervous system is linked to sexual arousal and desire pathways. The broad receptor profile is also presented as a reason for a wider adverse-effect profile.

Ipamorelin is reported to activate GHS-R1a, the ghrelin or growth hormone secretagogue receptor, on somatotroph cells in the anterior pituitary. The source links this receptor activity to Gq/phospholipase C signaling, IP3 generation, intracellular calcium release, and pulsatile release of stored growth hormone. It also describes ipamorelin as relatively selective in early characterization, with GH-releasing doses not meaningfully increasing ACTH, cortisol, prolactin, FSH, LH, or TSH. Because the mechanism relies on pituitary GH stores, the source indicates that pituitary function and normal feedback biology remain relevant to the response.

Typical dosing

250-500 mcg daily (loading), then 500-1,000 mcg weekly (maintenance) · Daily during loading (1-2 weeks), then weekly maintenance · Loading 1-2 weeks, then maintenance · Subcutaneous injection

200-300 mcg 2-3x daily · 2-3x daily

Research dosing

250-500 mcg initially · Loading phase 2-3 weeks, then maintenance · Subcutaneous injection

100-300 mcg per injection · 8-12 weeks typical · Subcutaneous injection

Typical duration

Loading phase 2-3 weeks, then maintenance

8-12 weeks typical

Administration

Subcutaneous injection

Timing

Evening or before sun exposure

With or without food

Before bed or morning, fasted

Fasted timing reported

Evidence level

Research

Clinical Trials

Possible side effects

Nausea (Reported as common, especially initially.)
Facial flushing
Fatigue

+6 more

Spontaneous penile erections
Darkening of skin and moles (Source highlights mole changes and pigmentation concerns.)
Priapism (Source flags this as an emergency-risk adverse event.)
Association with melanoma risk (Source links restricted status and dermatology cautions to melanoma risk concerns.)
Possible histamine release (Source advises caution for MCAS or histamine sensitivity.)
Legal restriction caution (Source reports illegality in the US, UK, and Australia; this regulatory claim needs admin review.)

Generally well tolerated (Reported by the source as a general tolerability statement, not a guarantee of safety.)
Injection-site reactions
Headache

+6 more

Nausea
Increased appetite
Water retention
Temporary joint stiffness (Source describes joint stiffness as temporary.)
No significant cortisol or prolactin elevation reported (Source presents this as a selectivity-related observation.)
Contraindicated with active malignancy (Listed by the source as a contraindication.)

Research summary

The supplied research summary describes narrow older human evidence for erectile-function outcomes. In men with organic erectile dysfunction, the source reports subjectively described erections after 12 of 19 Melanotan II injections compared with 1 of 21 placebo doses, plus longer rigidity periods and greater sexual interest; nausea and yawning were frequent. The source connects this effect profile to later bremelanotide development. For tanning, the same source emphasizes lack of large safety trials and dermatology concerns including changing moles, melanoma reports, uneven or lasting pigmentation changes, nausea, and risks from unregulated injected material.

The source identifies Raun et al. 1998 as early foundational work and describes characterization across rats, pigs, and isolated pituitary cells. It reports that ipamorelin released GH without corresponding ACTH or cortisol increases at doses above the GH-release threshold. The source also notes that human development reached Phase II for postoperative ileus before being discontinued for insufficient efficacy. For popular wellness uses such as anti-aging, fat loss, muscle gain, or recovery, the source states that large peer-reviewed human randomized trials are not available and that these claims are extrapolated from mechanism rather than established outcomes.

References

WikipediaMelanotan II PubMedPubMed record 11018622

+1 more

+1 more

Full profile