# Melanotan 2 Effects: What People Report and the Cited Safety Risks > Melanotan 2 effects in plain English: tanning, libido, appetite, and the real downsides — nausea, moles, and serious case reports — with cited safety cautions. What people actually report, kept clearly separate from what the cited studies have shown. ## The short version People chase **Melanotan 2** for one big reason: a deep tan fast, with little or no sun. That part is consistently reported and it's why the peptide exists. But it comes bundled. Men frequently report a sudden jump in sex drive and spontaneous erections; lots of people feel much less hungry; many feel sick to their stomach in the first hour. Skin effects go beyond an even tan — moles and freckles darken, new moles can appear, and lips, scars, and gums can go dark too. Below, the things people report are kept in their own clearly-labeled box, because reports from forums are not the same as proof. After that comes the safety section, where every caution is tied to a published study. The line we hold: we describe what's reported and what's cited — never a dose, never "you should." ## What people report **These are effects described by the research-use community — anecdotal, not clinical evidence, and not verified by controlled trials. No doses are given here.** **The upsides people seek** - **A rapid, deep tan with little sun** — very commonly described as the whole point. Users say skin darkens within days and they reach a deeper color with far less sun or sunbed time than usual. - **Feeling more attractive and confident** — commonly reported as the reason people keep going despite side effects. Some discussions note this can tip into preoccupation with appearance. - **Less appetite, some weight loss** — very commonly reported, sometimes from the first dose and within the hour. People split on whether they treat the appetite drop as a bonus or an unwanted effect. - **Higher libido and spontaneous erections (men)** — commonly reported by men, often from the first or second dose; women also report heightened arousal. Welcome to some, awkward to others when erections arrive at inconvenient times. **The downsides people report** - **Nausea, sometimes vomiting** — one of the most consistent reports, usually in the first hour after a dose and worst in the early days, often easing with time. - **Facial flushing and feeling hot** — commonly reported within minutes to an hour; usually brief. - **Darkening of existing moles and freckles** — very commonly reported, often the first visible sign anything is happening; spots stand out more sharply. - **New moles appearing** — a frequent and alarming report among longer-term users, sometimes many at once, occasionally within a day or two of a dose; often what sends people to a doctor. - **Dark patches on face, lips, scars, gums, and genital skin** — commonly reported; some describe melasma-like facial patches. - **An uneven, blotchy, or unnaturally long-lasting tan** — frequently reported, sometimes with an orange or grey cast, and color that lingers weeks to months after stopping and fades patchily. - **"Melanotan flu"** — a run-down, flu-like tiredness in the first days, commonly reported and usually fading with continued use. - **Injection-site redness, itching, bruising, or small lumps** — commonly reported with repeated injections; usually minor. - **A strong urge to stretch and yawn after a dose** — a distinctive, frequently mentioned sensation; described as odd but harmless. One belief worth flagging: some users assume a deeper color protects them from burning and stay out longer. That is a user belief, not demonstrated protection — many still report burning when they overdo the sun. ## Safety & cautions This is the genuinely useful part, and each point is tied to published work. **New, changing, or darkening moles — and melanoma.** Because Melanotan 2 drives pigment cells (melanocytes) throughout the skin, case reports describe bursts of new moles, atypical (dysplastic) moles, and darkening or change in existing ones during use [10][11][12][13]. Dermoscopy studies have measured real changes in moles while people use it [14], and several reports document melanoma and melanoma in situ arising in users [15][16][17]. The long-term cancer risk is not established, but it is a serious, case-reported concern — especially alongside sun or sunbed use [18][19]. Any new or changing mole during or after use is a reason to see a dermatologist promptly. **Rhabdomyolysis and kidney injury.** A published case links a Melanotan 2 injection to systemic toxicity with rhabdomyolysis — severe muscle breakdown that can poison the kidneys [20] — and a separate case with literature review describes renal (kidney) infarction tied to its use [21]. These point to potential for serious muscle and kidney harm; the mechanisms are not fully understood and may involve the peptide's effects on blood vessels. **Priapism.** Because melanocortin signaling promotes erections, several reports describe priapism — a prolonged, painful erection — after tanning injections, including after apparent overdose [22][23][24]. Priapism is a urological emergency; untreated, it can permanently damage erectile tissue. **PRES (a brain-swelling syndrome).** One report describes posterior reversible encephalopathy syndrome — brain swelling with headache, seizures, vision changes, and high blood pressure — in connection with melanotan use [25]. It fits with the compound's reported effects on blood pressure. **Blood pressure, heart, and that nausea.** In animal work, alpha-MSH-type agonists raise blood pressure, and the pressor effect worsens when nitric-oxide signaling is impaired [26][27]. Combined with the very commonly reported nausea [28], that points to meaningful heart and gut effects that are poorly mapped in people using unregulated product. **You don't know what's in the vial.** Lab analyses of melanotan bought online repeatedly find inaccurate labels, variable or unverifiable peptide content, and impurities [29][30], and it shows up in surveys of falsified and black-market injectables [31][32]. With no quality control, a buyer cannot know the real identity, dose, purity, or sterility of the contents [33][34] — which multiplies every other risk above. **No approval, unknown long-term safety.** Melanotan 2 has never been approved by any regulator for any use, and development never finished late-phase trials, so its long-term safety in humans is simply unknown [33][34]. Regulators and dermatology bodies have specifically warned against melanotan tanning products [35], and reviews of unregulated alpha-MSH-analog use catalogue the harms [36]. Treat it as an unapproved research chemical, not a medicine or cosmetic. **It is not the approved, distinct drugs.** Melanotan 2 is often confused with afamelanotide — an approved melanocortin therapy for the rare light-sensitivity disease erythropoietic protoporphyria [37][38] — and with the separately approved sexual-function melanocortin agonist developed from this peptide family [39]. Those approvals and their controlled safety data do **not** extend to Melanotan 2, a different, unapproved compound used without medical oversight [36]. ## Then and now Melanotan 2 was designed in the late 1980s at the University of Arizona as a super-strong copy of the pigment hormone alpha-MSH, meant to promote tanning and photoprotection — and so, the hope went, lower skin-cancer risk [36][40]. Early human work showed it could darken skin [4], researchers noticed it also triggered erections, which led to a small erectile-dysfunction study [5] and to a spin-off melanocortin agonist aimed at sexual dysfunction [39]. The original tanning program never reached the market. From the mid-2000s an illicit trade grew anyway, with the peptide sold online as unlicensed "sun-tan jabs" or the "Barbie drug" despite repeated regulator and dermatologist warnings [41][42]. It remains an unapproved research chemical with no sanctioned medical or cosmetic use. --- Bright, plain-English digests of the Melanotan 2 literature — the science and the risks, never a sales pitch or a prescription.