MT-2

Melanoma, cutaneous and mucosal. In one case report a 20-year-old woman with Fitzpatrick type II skin had a gluteal melanoma excised three months after a 3-to-4-week course of MT-2 self-injection taken to augment sunbed tanning. A second report describes melanoma in situ associated with an injectable melanotropic peptide sold as 'melanotan', the specific analogue not named in the record. A third describes a 22-year-old woman with a maxillary mucosal malignant melanoma after using an MT-2 nasal spray for tanning, treated by resection and ongoing immunotherapy.^15,16,17

as reported in individual case reports; there is no incidence rate for any of this, and causality is established in none of them

Eruptive and atypical (dysplastic) nevi, and darkening or growth of existing moles. A review of unregulated use of the alpha-MSH analogues melanotan I and II found melanocytic change in existing moles and newly emerging dysplastic nevi to be the chief reported cutaneous complications, and counted four case reports of melanoma emerging from existing moles during or shortly after melanotan use while stating that conclusive evidence linking them is lacking. A separate case report describes a 40-year-old man with prior melanoma and multiple dysplastic nevi who self-administered a synthetic alpha-MSH peptide, which the report does not identify as MT-2, and developed crops of clinically and histopathologically atypical nevi that lightened and lost growth features after he stopped.^7,18

as reported; described in the review as the chief cutaneous complication in the case literature, with no rate given and no causality established. The review covers melanotan I and melanotan II together and does not separate them

Rhabdomyolysis with sympathomimetic toxicity and renal injury. A 39-year-old man who self-injected internet-purchased MT-2, in a single quantity he described as several times his usual starting amount and later confirmed as MT-2 by mass spectrometry, presented with tachycardia, hypertension, mydriasis, diaphoresis and tremor, with creatinine 2.25 mg/dL on presentation and creatine kinase rising to 17,773 IU/L twelve hours later; he was discharged from intensive care after three days. A separate case report with literature review describes a renal infarction the authors considered most likely attributable to MT-2.^19,20

as reported in individual case reports; causality is not established in either, and the second is framed by its own authors as a possible cause

Priapism. A patient presented to the emergency department of a tertiary urology centre with acute low-flow priapism after abdominal subcutaneous injection of melanotan, which the report names without specifying the analogue. He was managed with cavernosal aspiration, irrigation and intracavernosal phenylephrine, avoided surgical shunting, and had not recovered erectile function at four-week follow-up.²¹

as reported in a single case report; causality is not established, and the analogue used is not specified in the record

Posterior reversible encephalopathy syndrome. A report indexed by PubMed as a case report and letter is titled 'Melanotan and the posterior reversible encephalopathy syndrome'. It carries no abstract in PubMed, and its title names 'melanotan' rather than melanotan II, so which analogue was involved cannot be determined from the record. Nothing beyond that reported association is asserted here.²²

as reported in a single published case report that has no abstract; causality is not established and the analogue is not specified

Acute symptoms in the early-phase human studies. Nausea, severe after 4 of 19 MT-2 injections in the 2000 organic-erectile-dysfunction crossover; a stretching-and-yawning complex; decreased appetite in the 1998 psychogenic crossover; and WHO grade II somnolence and fatigue in one of the two volunteers escalated to the highest level in the 1996 phase I study.^2,3,4

as reported; nausea and the stretching-and-yawning complex were more frequent after MT-2 than after placebo in both 10-man crossover studies