When sex no longer appeals to you
Could PT-141 help when you no longer want sex?
Losing interest in sex can bother you even when you feel well. This drug brought some women a slight return of desire, often with sickness.
What does the drug offer for lost interest?
You may want sex while your penis has trouble becoming firm enough. PT-141, also called bremelanotide, was mainly studied for the loss of desire.
This drug is called a peptide because several small parts are joined together. Similar parts form proteins, materials your body makes for skin, muscles, and other work.
The medicine changes how brain cells take part in your interest in sex. Approval covers certain women whose lost desire troubles them before their monthly periods end.
Their loss must last and have no other clear cause behind it. You aren't covered as a man, nor are women past the end of their periods.
What first led researchers to test PT-141 for desire?
A wish to have sex begins partly with activity inside your brain. PT-141 was made to act like a substance your brain normally uses for that activity [1].
PT-141's seven small parts are joined in a loop, rather than a straight line. That shape helps the medicine last; ordinary erection drugs instead help blood vessels widen [1] [11].
Men with erection trouble got erections quickly in early tests of PT-141. Larger tested amounts produced stronger erections, while rats and monkeys also developed erections during testing [1].
Female rats made more approaches to males, without changing their back-arching during mating [2]. They moved around as before; the main change concerned their approach to sex.
Later came stage 3 tests, meaning larger studies near the end of testing a medicine [3]. Those studies asked whether PT-141 helped women who found their loss of desire upsetting.
United States approval for bremelanotide shots followed in June 2019, for a narrow use [3] [11]. The women covered hadn't reached the permanent end of their monthly periods.
The women lacked desire across different partners, activities, and places, rather than in one setting. Another illness or other clear cause couldn't explain the loss of interest.
Early erection findings never led to approval of PT-141 for men [1]. If you need help with erections, the evidence differs from the evidence for desire.
Why is the PT-141 peptide shaped to last?
A shot puts medicine into your body, where the body starts breaking it down. The PT-141 peptide has seven parts joined into a closed loop [1].
Think of a short chain with its ends joined, instead of left open. That shape makes breakdown harder, allowing the drug to last long enough for a shot [1] [11].
The name PT-141 was used while researchers were developing the medicine. Bremelanotide names that same drug, so either name may appear in a study [3].
Those names identify one substance, with known contents in the approved medicine [11]. You may also see melanotan II, a related substance that differs chemically [1].
A result for melanotan II doesn't establish what bremelanotide will do. If you read claims treating these substances as interchangeable, that difference matters.
Testosterone is a hormone, made by your body to help control work in other organs [1] [11]. PT-141 doesn't directly increase that hormone, replace it, or act like an ordinary erection medicine.
Laboratory powders bearing the PT-141 name lack official checks of contents, strength, and cleanliness [11]. You can't tell from the name whether the powder matches the finished medicine.
Why did researchers focus on wanting sex?
Your brain uses substances made by your body to help control desire [1]. Researchers tried to copy one of those substances rather than add testosterone.
Work on melanotan II led toward PT-141, which has a small chemical difference [1]. Researchers then focused on whether the new drug changed the wish for sex.
Female rats became more inclined to approach males, while keeping their usual mating posture [2]. Their backs still arched during mating as they had before receiving the drug.
PT-141 became the first approved desire medicine to act on this group of brain switches [3] [12]. A cell switch reacts when certain substances reach that part of the cell.
Being first describes a new way to act, rather than a large benefit [3]. The women studied gained only a little desire, despite that new approach.
Related switches also take part in controlling hunger and making skin color [11]. A medicine reaching those switches can therefore affect eating or leave skin darker.
You might welcome renewed interest yet find the discomfort too troublesome. The small improvement and the sickness belong together when you judge the drug.
What links the brain findings to women’s desire?
Some cells inside your brain respond to substances involved in wanting sex. The main drug target is called the melanocortin 4 receptor, meaning a cell switch [1].
Another target, the melanocortin 3 receptor, contributes less to the same effect. Researchers think the drug's action there helps other brain cells create desire [11].
A study tested 31 women whose periods hadn't ended and whose low desire troubled them. Each woman received both the medicine and a placebo, a treatment with no active drug.
Women reported more desire for up to 24 hours after receiving PT-141. Scans also showed stronger links between brain areas handling feelings and bodily sensations [5].
The scans found changed activity in brain areas controlling movement, without showing better movement. The scans show you where the drug acted during the viewing task.
The how PT-141 works page follows that connection between brain activity and desire. You can read more there about the PT-141 mechanism of action, meaning how the drug produces its effects.
How can you judge help alongside unwanted effects?
The main evidence came from two stage 3 studies, meaning the major tests before approval. Women felt a little more interest and a little less troubled about its loss [3] [4].
Feeling a little more interest didn't establish a return to a satisfying sex life. Researchers questioned whether women felt enough relief for daily life to improve much.
You can trace the figures to published papers or the official medicine leaflet. The references let you find the paper supporting each numbered claim.
Among PT-141 side effects, sickness was especially common, with redness and headaches also reported. Pressure can also briefly rise, and skin can darken; both add concerns for you.
People describing their own use online may sound much more certain about benefits. When you read those accounts, remember that nobody compared treatments to check the cause.
What do personal accounts add to the studies?
Some describe more desire after trying the drug; others describe feeling sick. Their accounts tell you what they felt, without establishing the cause.