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Enjoy sex like you used to

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Erectile Dysfunction
Premature Ejaculation
Low Testosterone
Retrograde Ejaculation
Pelvic Floor Dysfunction
Anorgasmia
For men who don’t respond to oral erectile dysfunction medications like Viagra®, Trimix injections can be a game-changer. It’s an injectable ED medication you insert directly into the side of the penis to help improve blood flow for better erections.
If reading “injection into the side of the penis” makes you squirm, we get it. Trimix’s method can seem daunting, but when it’s used correctly, it can make a big difference in your sexual health. It’s also the safer choice than the shady gas station sex pills you might be considering.
Below, we’ve shared what science says about how Trimix injections work, their effectiveness, and potential side effects.
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Trimix is an injectable medication containing three active ingredients: alprostadil, papaverine, and phentolamine.
Alprostadil is the most important of these — it’s a vasodilator, which means it widens your blood vessels to increase blood flow to your erectile tissues. Alprostadil, on its own, is approved by the Food and Drug Administration (FDA) to treat erectile dysfunction and is sold under the brand name Caverject®.
(Hot tip: if you want to stop reading about penile injections now, you should know that alprostadil is also available in a cream, gel or urethral suppository,.)
The other two compounds in Trimix medication are papaverine and phentolamine.
Papaverine is a phosphodiesterase-5 (PDE) inhibitor that keeps your erection from going soft by blocking a compound that reduces blood flow, similar to medications like Viagra and Cialis®.
Phentolamine, on the other hand, is an alpha-blocker. It also increases blood flow, which can positively affect your erections.
Together, these medications amount to a triple threat against erectile dysfunction, or at least that’s what some research says.
Before it’s time for sex, Trimix should be administered into the corpora cavernosa, which is the two chambers of spongy tissue in the penis that fill with blood to create an erection. The chambers communicate so an injection on one side will deliver medication to both corpora. After the injection, the user (that’d be you) needs to apply pressure to the injection site for a few minutes.
Within five to 20 minutes, you should get an erection that will peak about half an hour after the injection. In most cases, your erection will disappear after an hour.
We say “should” and “in most cases” partly because the FDA hasn’t approved Trimix for ED. Much of our info comes from the FDA’s approval of alprostadil for ED and manufacturer information.
Alprostadil, on its own, is FDA-approved, meaning it has passed clinical trials showing it is safe and effective for the treatment of erectile dysfunction.
But Trimix isn’t a drug with just a single active ingredient. It’s a compounded medication produced at compounding pharmacies, which are usually more expensive.
Although the dose of each mixed ingredient may vary compared to when each is a single active ingredient, research suggests that Trimix’s efficacy is similar to that of alprostadil.
When it comes to Trimix injection reviews, users in a prostate cancer message board on Mayo Clinic Connect shared that the drug had been helpful when other ED treatments failed or had uncomfortable side effects. Some said the injection only felt like a “pinch,” while others complained of “throbbing” sensations. And some men said their erections lasted even after ejaculating.
We know that alprostadil can cause side effects, including:
Dizziness and headache
Rash or swelling of the penis
Hypotension or hypertension
Penile infections
Injuries to the penis
Penile function issues like prolonged erection (priapism)
Another potential side effect of alprostadil is penile fibrosis — a type of scarring that can reduce the penis’s elasticity. Penile fibrosis can cause anatomical deformation, which is a complicated way of saying it could cause your penis to curve.
Papaverine can also cause penile fibrosis. As for phentolamine, it is rarely used in injections by itself, so our picture of its side effects is blurry at best.
Because this medication is typically taken as a self-injection, it’s important to understand the proper technique and location for injections. This will help you avoid tissue damage and other potential issues.
Any intracavernosal injection could lead to injuries with the wrong injection technique, so have a urology expert, urologist, or other trained healthcare professional show you how to safely remove the needle from the rubber stopper, hold your penis between your thumb and index finger, and properly apply pressure to the plunger.
And don’t forget to sterilize — before injecting, be sure you clean the area with an alcohol swab.
A healthcare professional can give you the most comprehensive advice, but we have to make sure you know to never inject Trimix into the top or bottom of your penis or any veins.
Even once you start injecting Trimix yourself, always seek medical advice if you’re unsure what to do.
Before jumping to injections, you’ll want to try other management options. Plus, sexual activity is an essential part of men’s health, and unless you and your partner have a calendar invite for sex o’clock blocked off, it’s not always predictable. Carrying a syringe around “in case” isn’t very practical.
Other options could include:
Treatment for underlying health conditions, like hypertension or diabetes
Dietary changes
Increased exercise
Therapy for psychological causes of ED
Quitting smoking
Reducing drinking
The most commonly prescribed ED pills are phosphodiesterase-5 inhibitors (PDE5 inhibitors), which relax arterial smooth muscle to increase blood flow to your penis.
Drugs like tadalafil and sildenafil (you probably know them as Cialis and Viagra), Stendra® (avanafil), and Levitra® (vardenafil) all fall into this category. There are also more discreet options like Hims hard mints, a chewable ED med that contains both Sildenafil and Tadalafil.
Health risks aside, Trimix is usually not a first-line option for ED treatment. But if you’ve seen those other treatments fail, Trimix might help you.
If you decide to use Trimix for ED, be sure to take precautions:
Only use Trimix as prescribed. Be sure you follow instructions from a health professional on injecting Trimix safely.
Practice good hygiene. Make sure to sterilize the skin with an alcohol pad before injecting.
Monitor your reaction. If your full erection doesn’t go away after four hours, head to the emergency room and seek medical care.
Trimix injections for erectile dysfunction are a potentially effective and safe second-line treatment for men who don’t respond well to other ED treatments. If you’re game for penile injection therapy, talk to your healthcare provider about your options.
If you’re unsure where to start, it may be time to schedule a call with a healthcare professional.
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