Skip to main content
QuadMix vs. Trimix: Choose the Right ED Injection for You
Erectile Dysfunction

QuadMix vs. Trimix: Choose the Right ED Injection for You

Quadmix vs. Trimix—both products are penile injectables that treat erectile dysfunction (ED), a condition that affects approximately 30 million men in the United States,1 with nearly a quarter of men with ED being under the age of 40.2  ED is a common treatable condition that has many potential causes and treatment options.

Most men seeking treatment start with phosphodiesterase class 5 (PDE-5) inhibitors such as Cialis and Viagra. Trimix and Quadmix are second-line treatment options for men who experience side effects with PDE-5 inhibitors or do not have satisfactory treatment results.3  Approximately 22% to 35% of men report that they are not helped or have a medical contraindication to using oral ED medications.4 Injectable medications have been used since 1983 to treat ED and are considered the most effective non-surgical solution for ED, according to the American Urological Association.5

What is the difference between Trimix and Quadmix?

Trimix is a mixture of three medications: papaverine, phentolamine, and prostaglandin. It is about 80% effective in helping men get and maintain an erection.3 Quadmix includes these three medications plus atropine. Most men start with Trimix and move to Quadmix if it is ineffective. According to the American Urological Association, the success rate for penile injections ranges from 53.7% to 100% without marked differences across medication combinations — satisfaction rates for penile injections as a treatment option for ED range from 46.3% to 98.8%.6 


Papaverine is a vasodilator. It widens blood vessels entering the penis and increases blood flow by inhibiting PDE5 (works similarly to oral ED medications). Papaverine is not used alone for penile injections.


Phentolamine relaxes the smooth muscle lining blood vessels by reducing the activity of the sympathetic nervous system. Phentolamine is not used alone for penile injections.

Prostaglandin E1

Prostaglandin E1 relaxes the smooth muscle lining blood vessels, which increases blood flow into the penis by increasing cAMP levels. Prostaglandin (alprostadil) is FDA-approved to treat ED. 


Atropine is used in conjunction with other medications to treat ED. Atropine inhibits nervous system receptors that control smooth muscle relaxation.

Quadmix and Trimix are available only by prescription, and the medication is prepared by a specialized compounding pharmacy. This allows physicians to customize penile injection therapy for each patient. The goal of treatment is to use the minimum effective dose that helps a man get and maintain an erection suitable for penetrative sex. Trimix and Quadmix do not impact libido, prevent pregnancy, or protect against sexually transmitted infections.

Is Quadmix better than Trimix?

No, Quadmix is not better than Trimix. Quadmix contains papaverine, phentolamine, prostaglandin, and atropine. Trimix contains papaverine, phentolamine, prostaglandin. Quadmix is sometimes prescribed for men who do not get adequate results from Trimix.

How long does Quadmix last compared to Trimix?

Trimix and Quadmix should produce an erection within 5 to 20 minutes, and an erection should last for about 30 to 60 minutes. Depending on your age, overall health, and medication dose, an erection can last longer.

How often can you inject Quadmix vs. Trimix?

Trimix and Quadmix should never be used more than once in 24 hours, more than two days in a row, or more than two to three times a week. Using Trimix or Quadmix with oral ED medications increases the risk of adverse effects, such as priapism. Advise your healthcare provider if you have taken any oral ED medications the week before the intended use of Trimix or Quadmix.

man with clock and ED pills

Don’t penile injections hurt?

Penile injections are administered using a short, fine needle into the side of the penis. Men who learn proper injection techniques and apply pressure afterward experience minimal pain and bruising. In a study of 65 men, on a score of 1 to 10, men rated the pain from injection 0.8 out of 10 with a range of 0 to 3, and 40 percent reported no pain. Study participants rated the pain from the medication being injected as 1 out of 10, with a range of zero to five, with 64.6 percent reporting no pain.7 In another study, 12-15% of men reported pain with injection. Most men reported decreased pain throughout treatment.8

A smiling doctor

Erectile dysfunction is very common. Most men experience it at some point in their lives. Even though very effective treatments are available, in a study that enrolled six million men, only 25% of men with ED actually received treatment.9 Even if you are not interested in treatment, talk with your doctor about your ED symptoms. Symptoms of ED generally precede symptoms of cardiovascular disease by five years.10

Lifestyle changes can improve your ED symptoms and potentially reduce your heart disease or stroke risk. Talk to an Invigor Medical treatment specialist today to learn more about ED treatment options.

Learn more about buying Trimix injections online.


While we strive to always provide accurate, current, and safe advice in all of our articles and guides, it’s important to stress that they are no substitute for medical advice from a doctor or healthcare provider. You should always consult a practicing professional who can diagnose your specific case. The content we’ve included in this guide is merely meant to be informational and does not constitute medical advice.


1. Nunes KP, Labazi H, Webb RC. New insights into hypertension-associated erectile dysfunction. Curr Opin Nephrol Hypertens. Mar 2012;21(2):163-70. doi:10.1097/MNH.0b013e32835021bd

2. Capogrosso P, Colicchia M, Ventimiglia E, et al. One Patient Out of Four with Newly Diagnosed Erectile Dysfunction Is a Young Man—Worrisome Picture from the Everyday Clinical Practice. The Journal of Sexual Medicine. 2013;10(7):1833-1841. doi:

3. Coombs, P. G., Heck, M., Guhring, P., Narus, J., & Mulhall, J. P. (2012). A review of outcomes of an intracavernosal injection therapy programme. BJU International, 110(11), 1787–1791.

4. Guay AT, Perez JB, Jacobson J, et al. Efficacy and safety of sildenafil citrate for treatment of erectile dysfunction in a population with associated organic risk factors. J Androl. 2001;22:793–7.

5. American Urological Association. (2018). Erectile Dysfunction: AUA Guidelines. Retrieved from

6. Burnett AL, Nehra A, Breau RH et al: Erectile dysfunction: AUA guideline. J Urol 2018; 200: 633.

7. Albaugh, J. and Ferrans, C.E. (2009), ORIGINAL RESEARCH—ED PHARMACOTHERAPY: Patient‐Reported Pain with Initial Intracavernosal Injection. The Journal of Sexual Medicine, 6: 513-519.

8. Bennarchik, C. Kottwitz, M. & Geiger, S. (2010). Self-injection, Transurethral, and Topical therapy in Erectile Dysfunction.

9. Doherty K. Most men with erectile dysfunction don’t seem to get treatment. Medical Express.

10. Zelefsky MJ, Shasha D, Branco RD et al: Pro-phylactic sildenafil citrate improves select as-pects of sexual function in men treated with radiotherapy for prostate cancer. J Urol 2014;192:868

This Article

Published: Jun 18, 2023


Article Categories

More Questions?
Fill out the form below, and one of our treatment specialists will contact you.

Featured Articles

TRT: Separating Myths And Truths

Over 40% of men over the age of 40 suffer from symptoms of low testosterone levels such as low sex drive, erectile dysfunction, lack of energy, depression, and an increase in percent body fat. Shou…

Why Is Obesity Considered a Disease?

In the United States, about 42% of all adults live with obesity, and two-thirds of U.S. adults meet the body mass index (BMI) criteria for overweight (>25 kg/m2) or obesity (>30 kg/m2).1,2 Ac…

Meet…Your Immune System

Most people seem to conceptualize their immune system as some sort of abstract defense against invaders that cause things like the cold or the even-more-dreaded flu…