MELANOTAN II

Peptide Data Sheet for Pharmacists and Compounding Professionals

BASIC INFORMATION

Name: Melanotan II (MT-II)
Class: Synthetic analog of alpha-melanocyte-stimulating hormone (α-MSH)
Structure: Cyclic heptapeptide analog of α-MSH
Molecular Weight: 1024.2 g/mol
Sequence: Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂
Chemical Modifications:

  • C-terminal amidation
  • Contains non-natural amino acids (Nle, D-Phe)

Available Forms:

  • Research peptide
  • Not available as an FDA-approved medication
  • Compounded formulations (subject to regulatory restrictions and safety concerns)

REGULATORY STATUS

FDA Status

  • Not FDA-approved for any medical condition
  • Classified as a research compound
  • Warnings against its use have been issued from the US, UK, and several other countries due to safety concerns and lack of regulation.
  • Not a legitimate dietary ingredient and cannot legally be used in dietary supplements.

Legal Considerations

  • Unlicensed and largely untested for human use.
  • Sale and distribution for human use are illegal in many jurisdictions.
  • Often marketed “for research purposes only,” which does not make it safe or legal for human consumption.
  • Compounding pharmacies should be aware of the significant safety concerns and lack of FDA approval.

MECHANISM OF ACTION

Melanotan II is a synthetic analog of α-MSH that:

  • Non-selectively binds to and activates melanocortin receptors (MC1R, MC3R, MC4R, and MC5R).
  • MC1R Activation: Stimulates melanocytes to produce melanin, leading to skin pigmentation (tanning).
  • MC3R and MC4R Activation: Implicated in sexual function (increased libido, erectile function) and appetite regulation.
  • MC5R Activation: Role less defined but involved in exocrine gland function.

Due to its non-selective binding, Melanotan II can affect multiple physiological systems beyond skin pigmentation.

Mechanism of Action

PHARMACOKINETICS

| Parameter | Value | Notes | |———–|——-|——-| | Absorption | Rapid after subcutaneous injection | Bioavailability not well characterized | | Distribution | Limited human data available | Acts on melanocortin receptors in various tissues | | Metabolism | Likely enzymatic degradation | Specific pathways not well characterized | | Elimination | Half-life: Not well established in humans | Limited human pharmacokinetic data |

Note: Pharmacokinetic data is primarily derived from limited studies and animal research; human data is scarce.

POTENTIAL APPLICATIONS (INVESTIGATIONAL/UNAPPROVED)

Note: All applications are investigational and not FDA-approved. This information is provided for educational purposes only, highlighting areas of research and illicit use.

Primary Illicit Uses

  • Skin Tanning: To achieve a tan without UV exposure.
  • Sexual Dysfunction: To enhance libido and erectile function (related to PT-141, which is a metabolite).

Other Investigational Areas (Limited Evidence)

  • Appetite suppression and weight loss
  • Rosacea (theoretical, due to anti-inflammatory effects of α-MSH)
  • Fibromyalgia (anecdotal)

ADMINISTRATION (ILLICIT/INVESTIGATIONAL)

Routes

  • Subcutaneous injection (most common)
  • Nasal spray (less common, variable absorption)

Investigational/Illicit Dosing

Note: No established safe or effective dosing regimen exists. The following information is based on unregulated use and research protocols and is not a recommendation for clinical use.

| Purpose | Investigational Dose Range | Frequency | |———|—————————-|———–| | Tanning | 0.025 mg/kg or 250-1000 mcg | Daily or every other day initially, then less frequently for maintenance | | Erectile Dysfunction | 0.025 mg/kg or 500-1000 mcg | As needed, prior to sexual activity |

SAFETY PROFILE

Reported Adverse Effects

Note: Safety data is limited and primarily from anecdotal reports, case studies of adverse events, and animal studies. Products are often unregulated and may be contaminated.

| System | Adverse Effects | |——–|—————-| | Gastrointestinal | Nausea (very common), vomiting, stomach cramps, decreased appetite | | Neurological | Headache, dizziness, fatigue, yawning, stretching complex | | Cardiovascular | Facial flushing, increased heart rate, palpitations, transient hypertension | | Dermatological | Darkening of existing moles, development of new moles, atypical melanocytic nevi, melanonychia (nail pigmentation), injection site reactions (pain, redness, bruising) | | Genitourinary | Spontaneous erections (priapism in some cases) | | Psychiatric | Mood changes, anxiety |

Potential Risks and Concerns

  • Increased Risk of Melanoma: Significant concern due to stimulation of melanocytes and changes in moles.
  • Rhabdomyolysis: Potentially fatal muscle breakdown (rare cases reported).
  • Renal Infarction/Kidney Damage: Rare but serious cases reported.
  • Encephalopathy Syndrome: Rare cases reported.
  • Systemic Infections: Due to non-sterile injection practices or contaminated products.
  • Unknown Long-Term Effects: Lack of rigorous clinical trials.
  • Product Quality and Purity: Illicitly sourced products may be impure, incorrectly dosed, or contaminated.

Contraindications (Theoretical/Based on Risk Profile)

  • History of melanoma or other skin cancers
  • Atypical moles or numerous moles
  • Cardiovascular disease
  • Kidney disease
  • Pregnancy and lactation
  • Children and adolescents
  • Psychiatric disorders

SPECIAL POPULATIONS

Pregnancy and Lactation

  • No human data available.
  • Strongly advised against use due to unknown risks and potential harm.

Pediatric

  • No human data available.
  • Strongly advised against use.

Geriatric

  • No specific data available.
  • Potentially higher risk of cardiovascular and other adverse effects.

PHARMACIST GUIDANCE

Compounding Considerations

  • Not Recommended: Due to significant safety concerns, lack of FDA approval, and the availability of illicit, unregulated products, compounding Melanotan II is generally not advisable and may carry legal and ethical risks.
  • Pharmacists should be aware of regulatory warnings and the potential dangers associated with this peptide.
  • If legally permissible and ethically justifiable in a specific, highly controlled research context (not for general dispensing):
    • Requires aseptic technique and sterile compounding environment.
    • Adhere to USP <797> standards for sterile compounding.

Storage and Handling (Research Settings)

  • Store lyophilized peptide at -20°C.
  • Reconstituted solutions typically stored at 2-8°C.
  • Use within a short period after reconstitution (e.g., 14-30 days, stability varies).
  • Avoid repeated freeze-thaw cycles.
  • Protect from light.

Patient Counseling Points (If a patient inquires or admits use)

  • Emphasize Lack of Approval and Safety Data: Not FDA-approved for any indication; limited safety and efficacy data in humans.
  • Highlight Serious Risks: Potential for skin cancer, cardiovascular events, kidney damage, and other severe side effects.
  • Warn About Unregulated Products: Illicitly sourced products may be contaminated or incorrectly dosed.
  • Discourage Use: Strongly advise against using Melanotan II for tanning or other unapproved uses.
  • Recommend Consultation: Advise consultation with a healthcare provider for approved and safer alternatives for their concerns (e.g., sunless tanners, treatments for sexual dysfunction).
  • Report Adverse Events: Encourage reporting of any adverse effects if they have used the product.

ETHICAL AND PROFESSIONAL CONSIDERATIONS

For Pharmacists

  • Prioritize Patient Safety: Counsel patients about the dangers of Melanotan II.
  • Adhere to Regulations: Understand and comply with all federal and state laws regarding unapproved drugs.
  • Professional Integrity: Avoid any involvement in the illicit promotion or distribution of Melanotan II.
  • Liability: Be aware of potential liability associated with unapproved and potentially harmful substances.

REFERENCES

  1. DermNet NZ. Melanotan II. https://dermnetnz.org/topics/melanotan-ii
  2. RxList. Melanotan-ii: Health Benefits, Side Effects, Uses, Dose & Precautions. https://www.rxlist.com/supplements/melanotan-ii.htm
  3. Evans-Brown M, et al. Use of melanotan I and II in the general population. BMJ. 2009;338:b566.
  4. Therapeutic Goods Administration (TGA), Australia. Safety alert: Melanotan-II injections. (Various alerts issued).
  5. Hjuler KF, Lorentzen HF. Melanoma associated with the use of melanotan-II. Dermatology. 2014;228:34–6.
  6. Nelson ME, et al. Melanotan II injection resulting in systemic toxicity and rhabdomyolysis. Clin Toxicol (Phila). 2012;50(10):1141-2.