Dangerous Viagra Interactions?

Viagra has been on the market for a long time now. Its status of the most popular impotence pill is responsible for numerous studies aimed at identifying potential side effects or dangerous drug interactions. As of now, the present body of knowledge draws attentions to numerous types of medication that can cause issues with your Viagra treatment.

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What Types of Medicines are Dangerous?

While prescription and non-prescription drugs, medications for the treatment of serious conditions as well as herbal remedies can cause different problems, most of them revolve around sildenafil’s (Viagra’s active ingredient) mechanism of action and its impact on the cardiovascular system. For others, the only noticeable impact might be diminished effect of Viagra, which doesn’t pose a danger but is a nuisance none the less.

In this article, we will consider some of the identified substances that have been confirmed to interact with Viagra in one way or another.

Nitrates

Nitrates are class of pharmaceutical substances that are commonly used to treat or prevent heart pain caused by a disease of the cardiovascular system, usually by diseases of the arteries in the heart. Some of the most commonly prescribed generic nitrates prescribed include the following:

• Nitro-glycerine
• Glyceryl Trinitrate
• Isosorbide Mononitrate
• Nicorandil

Note that the medicines listed here are generic names of active substances, available under different brand names in different countries of the world, so you should be careful to read the ingredients if you suspect some of the medicines you might be using falls within this group.

How Nitrates and Viagra Interact?

The dangerous interaction between sildenafil, Viagra’s active ingredients and nitrate-based medicines has been highlighted by the Viagra manufacturer, Pfizer, as well as by the EMA and FDA. The root cause of this interaction is the fact that both Viagra and nitrate-based drugs cause smooth muscles that control the flow of blood through arteries to relax. ¹ When that happens, blood vessels will expand, blood pressure will drop and the pulse is highly likely to speed up in order to compensate for a decrease in blood pressure.

If Viagra is taken at the same time as let’s say, nitro-glycerine, the combined effects could be dangerous and severe enough to cause serious heart problems, including heart attack. This is why it is very important to avoid using Viagra if you’re already using some nitrate-based medicine for treatment of cardiovascular issues. If that is the case, it’s is highly recommended to talk to your doctor so he could inform you about the safe way you can use ED pills, without risking damage to your heart.

Alpha-blockers and Viagra

Alpha-Blockers are a type of pharmacological agents that act as antagonists on α-adrenergic receptors. They have been used for decades in autonomic nervous system research and are prescribed today as a treatment for a number of conditions including hypertension, Raynaud’s disease, congestive heart failure, erectile dysfunction and benign prostatic hyperplasia. The alpha-blockers most commonly prescribed today include:

• Doxazosin (Cardura)
• Prazosin
• Terazosin (Hytrin)
• Tamsulosin (Flomax)
• Alfuzosin (Uroxatral)
• Silodosin (Rapaflo)

Why is it dangerous to mix Viagra and alpha-blockers?

Alpha-blockers, similarly to nitrates relax smooth muscles, thus enabling smaller blood vessels to expand. They achieve this by inhibiting α receptors in the arteries and smooth muscle tissue, thus preventing the hormone noradrenaline from tightening those muscles. One study especially highlights the dangers of this interaction when alpha-blockers are used to treat benign prostatic hyperplasia. ² This article is based on the fact that prostate problems are commonly accompanied by ED, so this kind of interaction isn’t that rare.

Similarly to nitrates, mixing Viagra and alpha-blockers can lead to a sudden and severe drop in blood pressure, causing the heart to overcompensate with increased heart rate with potentially life-threatening consequences.

Viagra and other impotence pills

While it might sound like a good idea to mix Viagra with other impotence pills, especially those like Cialis which have significantly longer duration than Viagra, this is one of the most dangerous interaction identified. Due to the fact that practically all of the available ED pills belong to the PDE-5 class and thus have a similar mechanism of action, mixing them is, for all intents and purposes, the same as overdosing on one brand.

The PDE-5 overdose will produce the same symptoms already described above – the sudden drop in blood pressure and the heart over-compensating for that. Needless to say, it can lead to the same, rather serious consequences.

Is it safe to use Viagra with natural remedies?

This is a tricky question, mostly because of the fact that there is relatively little to no research in possible interactions between Viagra and substances that belong to the category broadly defined as natural remedies. However, one exception to this is St. John’s wort (Hypericum perforatum) which has been used for decades as a mild antidepressant.

However, St. John’s wort is also known to cause impotence problems with prolonged use. While some studies do suggest that Viagra can be very successful in remedying this problem ³ , at the same time, Hypericum perforatum is known to diminish the effects of Viagra by reducing the blood levels of the medicine and contribute to its faster elimination from the body.

Are there any foods or drinks that shouldn’t be used with Viagra?

There isn’t too much to say when talking about interactions between Viagra and certain foods or drinks. Things that are worth mentioning are the fact that it is best to avoid heavy, greasy meals for half an hour prior and after taking Viagra since it can diminish its effects or slow down the onset.

On the other hand, one type of food that should be avoided is – grapefruit. For reasons that still aren’t completely determined, grapefruit can interact with dozens of different medicines and recreational drugs, including Viagra.

While there is still no consensus regarding the root cause of this interaction, furanocoumarin, a substance that is found in both grapefruit and tangelo is the most likely culprit. This chemical binds to a specific enzyme in the intestinal tract, thus preventing absorption of certain substances, prolonging and maintaining their blood levels at the higher concentration.

What about mixing Viagra and recreational drugs?

As a rule of thumb, it is best not to mix any substance with illegal narcotics, mostly due to the fact that potential interactions and unwanted side effects have not been researched in details. However, as is often the case, this doesn’t prevent certain individuals from taking Viagra in parallel with substances such as cannabis, alcohol or MDMA, sometimes in order to compensate for the negative effects, these illegal substances may have on the sexual drive.

Viagra and alcohol

While alcohol is probably the substance most commonly used alongside Viagra, mixing the two isn’t the best idea. First and foremost, alcohol is known to contribute to erectile dysfunction, so drinking while trying to manage your ED certainly isn’t the best idea. On the other hand, with blood pressure lowered by Viagra, the effects of alcohol intoxication can be exacerbated. What’s more, with alcohol dropping the blood pressure further down, unwanted side effects are likely to manifest.

Viagra and cannabis

It may sound strange, but this is actually a rather dangerous combination! The risks associated with it stem from the fact that both Viagra and cannabis are known for lowering the blood pressure, causing the heart to work faster in order to compensate. This would maybe remain just a note of caution if there wasn’t for one study that elaborated the case of a 41-year old man who used cannabis alongside Viagra and suffered a myocardial infarction due to the interaction of the two. ⁴

Viagra and stimulants (MDMA, Amphetamines, Cocaine)

A common drug combination, especially in nightclubs and at rave parties, the mix of Viagra and stimulants is very dangerous. While most of the interactions considered prior to this posed risk to the health of an individual due to “stacking” of lowering blood pressure effects, with stimulants, it’s different – Viagra will still drop the blood pressure so the heart will be more prone to work faster in order to compensate. When stimulants are introduced into the organism, the pulse will be significantly higher than normal and when that is combined with reduced heat regulation, heart attack or stroke become very real possibilities.

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