This in-depth guide on PT-141 peptide therapy was crafted by the research team at Peptides.org – the premier source for all information about research peptides, SARMs, and more.
Presenting as a disorder like erectile dysfunction or lack of libido, sexual dysfunction can hamper romantic relationships and self-esteem, leading to countless other issues.
Fortunately, researchers are continuously working on life-changing therapies to address sexual dysfunction.
The United States Food and Drug Administration (FDA) has recently approved PT-141 (bremelanotide) as a safe and effective medication for treating lack of sexual desire in premenopausal women. PT-141 is also investigated as a treatment for erectile dysfunction in men, with promising results to date.
PT-141 is a synthetic peptide that is commonly administered via subcutaneous injection or as a nasal spray. Both routes of administration have shown safety and efficacy in human research subjects, making PT-141 an in-demand peptide for sexual health research.
In this article, we discuss the clinical research on PT-141, and cover potential benefits, safety profile, dosing guidelines, and more.
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What is PT-141?
PT-141 is a synthetic peptide analog of alpha melanocyte-stimulating hormone (α-MSH), an endogenous neuropeptide best known for its role in stimulating melanogenesis, or the production of melanin.
A non-selective agonist of the melanocortin receptors, PT-141 binds notably to the melanocortin 3 and 4 receptors (MC3R, MC4R), which link to the modulation of sexual behavior and appetite [1].
In fact, extensive clinical research has shown that PT-141′s activity at MC3R and MC4R increases sexual desire in women with hypoactive sexual desire disorder (HSDD), a fairly common disorder that is characterized by a low or lack of sex drive in women [1, 2, 3].
Researchers have also explored the potential of PT-141 as a safe and effective treatment for erectile dysfunction in men, given the link between melanocortin receptor activation and penile erection [4, 5].
PT-141 was developed by Palatin Technologies, which made a small chemical modification to melanotan 2, also an alpha-MSH analog and of which PT-141 is a naturally occurring metabolite [1].
In the United States, PT-141 has been assigned the generic name “bremelanotide,” and is prescribed to HSDD patients as Vyleesi, a prefilled autoinjector pen that is self-administered by the patient [1, 2].
PT-141 products that are available for purchase online are strictly intended for use by qualified research professionals for laboratory experimentation only.
What Does PT-141 Do?
As a melanocortin receptor agonist, PT-141 initiates a physiological response in the subject upon making contact with the melanocortin receptors, located primarily in the midbrain. Both melanocortin receptors 3 and 4 are believed to play a key role in sexual desire and arousal in both males and females [1, 4].
PT-141 is believed to stimulate dopamine hormones that are linked to increased sexual desire; in men, this results in penile erection [6]. This mechanism may be considered advantageous to that of traditional erectile dysfunction (ED) treatments, such as Viagra, which are vasodilators that directly increase blood flow to the penis but require sexual arousal and stimulation to take effect [7].
In the case of women, PT-141 is also thought to work primarily through its activity at MC3R and MC4R, thus triggering the release of dopamine and increasing sexual desire [3]. Prior to the clinical use of PT-141 in women, the treatment of HSDD often included psychosocial and biological treatments, requiring consistent daily or weekly treatments. Fortunately, PT-141 can be taken on an as-needed basis, approximately 45 minutes prior to sexual activity via subcutaneous injection [2, 8].
PT-141 is therefore seen as a convenient treatment that does not require a long-term commitment.
PT-141 Benefits | Clinical Trials and Research
Extensive clinical research has been conducted to investigate the effects of PT-141 on several conditions, including erectile dysfunction, HSDD in premenopausal women, and even weight loss.
Here are some key research-backed findings and benefits of PT-141 administration.
PT-141 and Erectile Dysfunction
Researchers have demonstrated the therapeutic effectiveness of PT-141 in male subjects with erectile dysfunction, even in cases where other treatments failed.
In a 2004 study, researchers administered PT-141 injections to both healthy males and males with erectile dysfunction who had not been responding to Viagra. Doses of 1mg were sufficient to induce erection in the healthy males, while doses of 4mg or 6mg produced erection in the ED Viagra-non-responder group. The treatment was well-tolerated by all subjects, with the researchers concluding that the peptide is a promising treatment for male sexual dysfunction [9].
Intranasal administration of PT-141 has also been shown to produce positive outcomes in males with ED, this time in those who were Viagra-responsive. A double-blind, placebo-controlled study found that nasally administered PT-141 at doses greater than 7mg induced an erectile response in as little as 30 minutes following treatment, with no safety issues reported [4].
Likewise, a randomized, placebo-controlled study examined the effects of intranasal administration of PT-141 in Viagra-non-responsive ED patients. The PT-141 group was directed to self-administer a PT-141 dose of 10mg via nasal spray, prior to intercourse. The men taking PT-141 ultimately reported “significantly greater intercourse satisfaction” in comparison to those of the placebo group [11].
PT-141 and Female HSDD
Experts have estimated that approximately 10% of women in the United States suffer from low libido or a complete lack thereof. Referred to as hypoactive sexual desire disorder (HSDD), this lack of sex drive in women has been linked to hormonal imbalances and abnormal levels of dopamine and serotonin. PT-141, a melanocortin that is known to act on the excitatory pathway involved in female sexual response, was thus identified as a promising treatment of HSDD [1].
In two identical, 24-week phase 3 trials, researchers evaluated the safety and efficacy of PT-141 treatment in premenopausal women with HSDD. The PT-141 patient group was instructed to self-administer a dose of 1.75mg on an as-needed basis via subcutaneous injection. In both studies, PT-141 therapy significantly improved sexual desire and reduced HSDD-related distress in the women, with minimal side effects reported [11].
Following completion of the clinical trial program (RECONNECT), the FDA approved injectable PT-141 as treatment for HSDD in premenopausal women [1].
PT-141 and Improved Mood
As we covered above, PT-141 stimulates feelings of sexual desire, arousal, and satisfaction related to sexual activity.
Researchers have posited that these effects are accomplished via activation of the MC4R in the hypothalamus, leading to an increase in dopamine [5]. Since dopamine is associated with feelings of motivation and reward, researchers believe that PT-141 treatment could possibly elevate overall mood in subjects, including enhanced optimism bias [12, 13].
PT-141 and Weight Reduction
In addition to its role in modulating sexual desire, the MC4R has been linked to appetite regulation. When activated, the receptor can promote satiety or the feeling of fullness. Two phase one clinical trials evaluated the safety and efficacy of PT-141 treatment in obese female subjects, specifically looking to establish whether the peptide could reduce the subjects’ caloric intake and body weight [14].
In the 16-day trial period, subjects received either once-daily, twice-daily, or thrice-daily treatment of PT-141 via subcutaneous injection, or placebo. Upon completion of the two studies, 90% of the women in the thrice-daily group exhibited a greater reduction in body weight versus placebo, and the twice-daily group had a “significantly greater reduction” in body weight compared to placebo. The researchers submitted that PT-141′s activity at the MC4R gives it potential as a therapeutic agent in obese individuals [14].
PT-141 Safety and Side Effects
Extensive research into the role of PT-141 therapy in sexual disorders has found the peptide to be safe and well-tolerated in both male and female subjects [1, 2, 4, 9, 10, 11].
Both subcutaneous injection and intranasal administration of PT-141 have been shown to be safe with minimal side effects [4, 9, 10, 11]. In addition, PT-141 has limited drug-drug interactions and has no clinically significant interactions with alcohol, unlike vasodilator treatments for ED like Viagra and Cialis [2].
In a clinical study examining the effects of PT-141 treatment on erectile dysfunction, the most common adverse events that were observed included [4]:
Facial flushing
Nausea
Headaches
Other mild, but rarely occurring, side effects of PT-141 administration include drowsiness, vomiting, sweating, and lower back pain [15].
It is important to note that PT-141 administration may cause elevated liver enzymes, and rarely could result in acute liver injury [16, 17].
In addition, PT-141 has been reported to increase blood pressure and decrease heart rate, effects which are transient. Accordingly, clinicians recommend that the peptide not be administered to subjects with uncontrolled hypertension or cardiovascular disease [18].
Administration of PT-141 via subcutaneous injection may cause burning, itching, or inflammation at the injection site. Typically, these side effects are mild and dissipate quickly. Employing proper injection techniques and rotating the injection site may prevent these side effects from occurring.
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Is PT-141 Legal?
Where sold as a research chemical, PT-141 may be legally purchased by research professionals for laboratory experimentation only.
Researchers and laboratory professionals are well-advised to conduct due diligence on potential peptide vendors making a purpose. The team at Peptides.org advises to source only from online vendors who:
State clearly that their peptide products are intended for research, scientific, or educational use only, for handling only by qualified personnel;
Do not make any unsupported medical claims surrounding the use of their peptide products; and,
Publish third-party laboratory results to confirm the identity, purity, and quality of the peptide products listed for sale.
Apart from its availability as a research chemical to qualified researchers, PT-141 (bremelanotide) is also a legal, FDA-approved treatment for HSDD in premenopausal women. It is sold under the brand name Vyleesi, and may be obtained with a prescription from a medical doctor [1].
PT-141 was granted FDA approval in 2019 after extensive research into its safety and efficacy in women experiencing sexual dysfunction [19]. In the United States, the evaluation of new drugs by the FDA follows a rigorous process. A team of physicians, chemists, pharmacologists, and other science professionals conducts an extensive unbiased review of all data related to the new treatment. If the benefits of the therapy outweigh its potential risks or adverse events, then it is deemed safe and approved for sale [20].
There are specific eligibility criteria that must be met in order to obtain a PT-141 (bremelanotide) prescription. It is only available to premenopausal women with no history of cardiovascular disease [18]. It has not been approved for use in menopausal women or in men, and a full medical history must be verified in order to be eligible for this treatment.
In sum, PT-141 is legally available to qualified researchers as a research chemical, as well as to patients with an approved and duly evaluated medical need for the drug.
PT-141 Dosage and Cycle
When prescribed in its approved form, PT-141 (bremelanotide) comes with a prescribing information insert that outlines its dosage and administration. The recommended dose of PT-141 for premenopausal women with HSDD is 1.75mg. Each bremelanotide autoinjector pen is pre-filled with this amount and can be administered via subcutaneous injection in the abdomen or thigh [19].
As a research chemical, PT-141 is not sold with any official dosing guidelines. However, researchers may refer to the available literature on PT-141 for initial reference, particularly if looking to study the peptide’s effects on male erectile dysfunction. Based on the research, here is a reference PT-141 dosing protocol to that end:
PT-141 Dosage: Administer 2mg via subcutaneous injection into the abdomen or thigh, approximately 45 minutes prior to sexual activity [9].
Frequency: Subjects should be given no more than one dose per 24-hour period. It is not recommended to administer more than eight doses per month [19].
PT-141 Cycle: PT-141 peptide, when administered for sexual function purposes, is not cycled.
Notes: One 10mg vial of injectable PT-141 will yield five doses based on these guidelines.
Concerning the intranasal administration of PT-141, nasal spray formulas may vary in terms of how they are compounded, as well as the ingredients added to each preparation. These variables, along with potentially reduced bioavailability, could affect the dosage required to attain the same effect as with administering the peptide subcutaneously. Refer to the manufacturer’s guidelines, if any, when administering a PT-141 nasal spray.
PT-141 | Injectable vs. Nasal Spray
PT-141 therapy may be delivered using either of two routes of administration: subcutaneous injections or via nasal spray. Both methods have been shown to induce a positive therapeutic response in subjects with sexual dysfunction disorders.
Subcutaneous injection of PT-141 has been extensively studied in both males and females. Treatment with injectable PT-141 has been shown to induce significant erectile response in male subjects who previously reported no erectile activity after taking Viagra [9]. In premenopausal women with HSDD, injectable PT-141 has been shown to increase sexual desire and reduce distress related to low sexual desire [11].
Intranasal administration of PT-141 has been investigated in multiple research studies in male subjects with and without erectile dysfunction. In both healthy male subjects and Viagra-responsive erectile dysfunction patients, treatment with PT-141 nasal spray was shown to increase erectile activity within 30 minutes of administration with minimal side effects [4].
In another study, male subjects that were responsive to either Viagra or Levitra were treated with PT-141 intranasally. Researchers found that PT-141 treatment induced a greater erectile response when used alongside Viagra in comparison to treatment with Viagra alone [21].
The subcutaneous route of administration has 100% bioavailability, making it an effective way to deliver PT-141 [18]. On the other hand, intranasal delivery of PT-141 is convenient to administer and is non-invasive. In addition, intranasal administration may be able to cross the blood-brain barrier more effectively and reach the melanocortin receptors in the brain more rapidly than injectable PT-141 [22].
While there are ample research studies on the effectiveness of injectable PT-141 treatment, more clinical studies must be conducted to investigate the effectiveness of intranasally administered PT-141.
Where to Buy PT-141 Online? | 2024 Edition
It is not difficult to buy PT-141 online these days.
While PT-141 is available online from a variety of vendors, it is important to purchase only research-grade PT-141 to ensure safe and worthwhile experimentation.
At Peptides.org, we pride ourselves on recommending high-quality products that are backed by quality research studies and available at reasonable prices.
In our experience, this research peptides vendor is the best place to purchase injectable PT-141 online.
Here is what we appreciate about this top vendor:
99% Pure Peptides: They provide 99% purity peptides that undergo laboratory testing to ensure quality and lack of contamination. This vendor’s peptides are backed by a certificate of analysis outlining the data on each product lot.
Affordable Prices: One PT-141 10mg vial costs only $49.50 USD, but they also offer bundle options, in which researchers can save up to 10% when purchasing this product in bulk.
Convenient Shipping Policy: U.S. orders over $200 qualify for free shipping. In addition, this vendor ships internationally to select destinations, allowing research professionals from around the world to test this peptide.
While some vendors excel on injectable PT-141, our top pick of PT-141 nasal spray is by PureRawz, which includes the peptide hormone oxytocin, also associated with sexual arousal.
Here are a few reasons why we trust PureRawz:
Rigorous Laboratory Testing: PureRawz conducts both in-house and third-party laboratory testing on all of its peptide nasal spray products, assuring researchers that their materials are safe and pure. All products are backed by a certificate of analysis and a seal of authenticity.
24/7 Customer Support: The customer care team at PureRawz is available at any time to address any customer inquiries. Their customer service representatives are friendly, helpful, and knowledgeable, making it a priority to respond to email inquiries in a timely manner.
30-Day Return Policy: PureRawz is confident that research professionals will receive the highest quality and purest PT-141 nasal spray on the market. They allow a generous 30-day return policy if not happy with their products, making the purchase low-risk and stress-free.
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How to Reconstitute PT-141
PT-141 for injection is sold as a powder that must be reconstituted prior to administration via subcutaneous injection. Reconstitution is the process of adding a solvent to a dry ingredient to form a solution.
To reconstitute and correctly store PT-141, the lab will need a variety of equipment, including sterile vials, insulin needles, and bacteriostatic water, among other tools.
Here are some standard guidelines for reconstituting PT-141 powder using bacteriostatic water:
Begin by washing hands thoroughly with antibacterial soap.
Prepare the supplies that will be need. These include a vial of PT-141 powder, a vial of bacteriostatic water, alcohol wipes, a syringe, and a needle.
Using an alcohol swab, wipe the tops of the bacteriostatic water and PT-141 vials where researchers will insert the needle.
Attach the needle to the syringe, ensuring not to touch the needle with fingers to avoid contamination.
Insert the needle into the vial of bacteriostatic water and withdraw the required amount.
Slowly push on the plunger of the syringe to dispense the bacteriostatic water into the vial of PT-141 powder.
Gently rotate the vial to fully mix the contents. Do not stir or shake the vial. Should no longer see any powder in the PT-141 vial.
If performing an injection, follow the medical guidelines for subcutaneous injection into the abdomen or thigh.
If the reconstituted vial is not used right away, properly store the solution in the refrigerator for use within 30 days
PT-141 FAQ
How to Take PT-141
Research-grade PT-141 for injection will typically come in the form of a powder that must be reconstituted with a solvent, such as bacteriostatic water. There are also PT-141 nasal spray products formulated to avoid the step of reconstitution, and are typically sold in a ready-to-use state.
How is PT-141 Delivered
A reconstituted solution of PT-141 is administered via subcutaneous injection, typically into the subject’s belly fat. PT-141 nasal spray products are also available for intranasal administration, and are applied by spraying the solution into either of the subject’s nostrils.
Is PT-141 Dangerous?
No. Numerous peer-reviewed research studies and trials have established that PT-141 is safe with minimal side effects when used to treat sexual dysfunction in both men and women. It has been deemed by the FDA to be safe for use in premenopausal women with HSDD.
Is PT-141 a Steroid?
No. PT-141 is not an anabolic-androgenic steroid. It is a synthetically produced melanocortin peptide analog of the naturally occurring alpha-melanocyte stimulating hormone.
Does PT-141 Increase Testosterone?
No. Current research studies do not indicate that PT-141 plays any role in the production of testosterone.
Does PT-141 Build Muscle?
No. Current research studies do not support the idea that PT-141 plays any role in building muscle.
Does PT-141 Cause Weight Gain?
No. The research to date does not show that PT-141 causes weight gain. In fact, research has shown that PT-141 treatment may promote lower caloric intake, subsequently leading to weight loss.
PT-141 | Review
PT-141 is actively studied for potential therapeutic benefits like addressing male sexual dysfunction and inducing weight loss in obese patients. It has already gained FDA approval as a treatment of HSDD in premenopausal women. It has been shown to increase sexual desire in females via subcutaneous injection.
Across the clinical studies to date, PT-141 is well-tolerated and exhibits minimal side effects. Subject to the application of prudent dosing guidelines, its effects may be experienced within 30-45 minutes after administration and it may be applied either as a subcutaneous injection or a nasal spray.
Qualified research professionals looking to source research-grade PT-141 can find top-quality injectable PT-141 and PT-141 nasal spray here.
Both of these vendors provide both exceptional products and attentive customer service. Highly recommended.
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