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What are PDE 5 inhibitors, and do penis enlargement pills work?

Guest Contribution: Brendan Lovel

OK, let's get stuck right in here. What are PDE5 inhibitors?

PDE5 inhibitors are a type of medication that help with blood vessel dilation, and smooth muscle relaxation in your penis and your heart. In your penis this leads to an erection, and in your heart, it helps with pulmonary hypertension. In fact, that's how it was discovered in the first place, but we'll get to that later.

Your first consult with a sexologist

Before we get delve any deeper, let me tell you how the first consult with a male client in my clinic often goes. Let's call him John, he booked his first appointment months ago, and now he's finally sitting in the chair opposite me. He's looking around the room, looking at my fake penis 'Geoffrey', perhaps, and glancing down at his feet quite a lot. The clock ticks, and John is saying nothing…

"Hi John, how are you, can I ask what did you booked this consult for today?"

Definitely looking at his feet now. Tick, tock.

"Ah, I think I have erectile problems."


"OK, no problem John. This is happens a lot, in fact, did you know 1 in 3 men over 45 have this issue? And the probability gets higher as men age, too, so there's nothing to be embarrassed about in the least. Even young guys commonly have this issue. What have you tried so far?"

"I tried Viagra and it didn't work."

"OK, can I ask, did you wait one hour after taking it before stimulation?"

"Ah, no, I didn't."

"OK, and, did you know it works much better on an empty stomach?"

"No, I took it after we'd been out for dinner."

Then, I start explaining how these medications work, what the difference is, and how to properly see if they will work for him, before moving on to other solutions. It's not just as easy as popping that little blue pill and off you go!

Now because they give you an erection, they're also known as penis enlargement pills. They do NOT actually make your penis any bigger then it was before.

Nevertheless, how do 'penis enlargement pills' work?

Well, basically they cause the blood vessels in your penis to vasodilate (fancy word for opening up ) and the blood flows in. When the penis of full of blood it gets trapped, and hey presto, you have an erection.

When the job is done and it's time to put your fire helmet away, your penis creates a chemical called PDE5 which causes vasoconstriction (fancy word for squeezing smaller) and the blood flows out.

PDE5 inhibitors such as Viagra, Cialis, Spedra and Levitra slow down the production of PDE5, allowing your erection to be sustained for a longer period of time.

Now there are two main reasons for taking PDE5 inhibitors. First of all, as we know, to get and erection and have sexual intercourse, however the second, less well known reason is to keep your penis healthy, oxygenated, and the tissues perfused.

Now let's dig into penis pills, penis enlargement pills, oral strips & troches.

There are 4 main oral medications, or PDE5 inhibitors if you prefer, and these can all be presented in different ways - capsules, tablets, troches and oral strips.

  • 1 Sildenafil (Viagra)
  • 2 Tadalafil (Cialis)
  • 3 Vardenafil (Levitra)
  • 4 Avanafil (Spedra)

Oral strips and troches are taken orally, and go straight into your bloodstream through the mouth. Generally this means you have a good chance of avoiding some of the side effects, like reflux, and they also tend to act a bit quicker. Now if you see 'new oral strip technology' advertised, please be aware it's only the delivery method that's new, not the actual PDE5 inhibitors.

Various countries have their own approval processes with medication, and I'm afraid, you won't find troches, strips and gels available everywhere.

Prescriptions are also required in some countries, and in my opinion, that's a good thing.

There are a few contraindications (some life-threatening) with taking PDE5 inhibitors, and my recommendation would be that you should always check with a health professional, before beginning your own trial.


What's the story behind PDE5 inhibitors? The birth of the magic blue pill…

It was Viagra that started it all, the magic blue pill that was launched onto the market back in 1998, revolutionising the love life of millions all over the world. Within three months of launch Viagra had generated $400 million for Pfizer, and it's consistently put $1.8 billion in their coffers every year since.

There had never been anything like this before, and yet, it would never have happened without the observational skills of one particular nurse.

Pfizer were trialling a new drug - Sildenafil - that was supposed to dilate the heart's blood vessels to help treat cardiovascular issues. All was going according to plan, and the research was going well expect one nurse noticed the men involved in the trials, were often to be found lying on their stomachs, when they'd been left comfortably lying on their backs.

Eventually she started asking why this was, and they admitted they were embarrassed because they were getting erections. After further investigation, it turned out the heart wasn't the only place blood vessels were dilating, and a $1.8 Billion per annum drug was born.

One final thing you need to know about PDE5 inhibitors. They will not work if you have nerve damage in your penis.

The nerves that enervate erections need to be at least partially functioning, for PDE5 inhibitors to have any affect at all. So if you fall into any of the following categories, then don't waste your time, money or effort. You'll only end up disappointed and down about the whole situation, and that's the last thing you need.

PDE5 inhibitors won't work:
- immediately following prostate cancer surgery
- if you've had surgery, trauma, illness (such as Diabetes)
or radiation to your pelvic region that's damaged the nerves.

And if you're not sure, I'd always recommend you consult with a health professional before trying any of them anyway. So ask questions, find out what may, or may not work for you, then follow the proper advice.

If you have never tried any, give them all a crack and figure out what agrees with your body. Good Luck!

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