Erectile Dysfunction

Can Metformin Cause Erectile Dysfunction?

June 3, 2021

While there are plenty of highly effective treatments for the symptoms of erectile dysfunction, there is no permanent, single-shot cure.

The best way to treat ED is to prevent it from happening in the first place and address underlying medical conditions or risk factors that may be contributing. 

There are so many causes of erectile dysfunction, both physical and psychological, that this might be more difficult than it sounds. Lifestyle factors can contribute, including smoking and drinking, conditions like obesity or diabetes are commonly involved, and even medications can make ED worse.

If you're taking metformin and experiencing erectile dysfunction, it’s possible they may be connected. But the research isn't totally clear.

What Is Metformin?

Metformin is a prescription drug classified as a biguanide primarily used to treat type 2 diabetes. Some of the most popular brand names for metformin include Fortamet, Glucophage, Glumetza, and Riomet, but it can also be found in various combination drugs. 

Metformin is an oral drug available as a tablet, liquid, or extended release tablet that is taken daily. Depending on the size of the dose and the application method, it can be taken anywhere from one to three times daily, typically during meal time. In general, the doses will start small and increase over time. 

Metformin is not a cure for diabetes and is taken long term, possibly decades, in order to treat the effects of diabetes and metabolic disorders. 

Some of the common side effects of metformin include:

  • Abdominal pain
  • Bloating
  • Chest pain
  • Chills
  • Constipation
  • Diarrhea
  • Dizziness
  • Gas
  • Heartburn
  • Indigestion
  • Low blood sugar
  • Low levels of B12
  • Metallic taste
  • Muscle pain
  • Nail changes
  • Nausea
  • Skin flushing
  • Upper respiratory tract infection
  • Vomiting
  • Weakness
  • Weight loss

While metformin does have interactions with other drugs, they are typically minor and non-life threatening. Other medications that could have a negative impact when mixed with metformin are thiazide diuretics, quinolone antibiotics, verapamil, ethanol, and ioversol. 

How Does Metformin Work?

It’s estimated that nearly 34 million people in the United States have diabetes, with more than 90% having type 2 diabetes, also known as adult-onset diabetes and non-insulin-dependent diabetes. Type 2 diabetes is most often diagnosed in people that are overweight or obese and those who are not physically active. 

When someone has diabetes, they typically experience an overabundance of blood glucose, or blood sugar, due to the body's inability to properly process it. While blood glucose is the main source of energy for the body, too much of it can be dangerous. 

The pancreas creates insulin in order to regulate blood glucose in the body. With type 2 diabetes, there is an issue with how the insulin is made and/or used. Metformin is used, along with a specific diet and exercise program, in order to decrease the amount of blood sugar released by the liver, improve cell's ability to use insulin, and makes your gut absorb less sugar.

If blood glucose is too high and left untreated, it can result in kidney damage, blindness, nerve damage, gum disease, and loss of limbs, as well as a much higher risk of heart attack and stroke. 

Metformin and Erectile Dysfunction

Metformin is unlikely to directly cause erectile dysfunction. But it's more complicated than just that.

To begin, diabetes is a major risk factor for developing erectile dysfunction due to its effects on numerous physical systems and processes. Metformin is a common and effective treatment for diabetes. Sorting through which is causing ED is not easy.  

In one study, metformin was shown to lead to a significant reduction in testosterone levels and sex drive in men with type 2 diabetes, both of which can contribute to erectile dysfunction.

At the same time, however, other research has suggested that metformin may improve the symptoms of ED due to its impact on the arterial system. 

Another small study found that metformin added to sildenafil (Viagra) treatment in non-diabetic men improved their sexual outcomes compared to men who received a placebo with sildenafil. Researchers concluded: "Further research in this area should seek to expand our understanding of this unique yet relevant relationship between insulin resistance, [Nitric Oxide] regulation and ED by conducting randomized trials with larger sample sizes specifically evaluating metformin use and its effects on erectile function..."

Whether metformin causes ED is complicated because metformin treatment is so frequent in diabetic men, who are already at greater risk for ED. The link to testosterone muddies the water further, so it's unclear whether metformin causes erectile dysfunction directly. There have been few studies on the potential sexual side effects of metformin.

What we do know conclusively is that diabetes plays an important role in erectile dysfunction. 

Diabetes and Erectile Dysfunction

Diabetes is one of the leading causes of erectile dysfunction, with numerous studies pointing to diabetes as a key risk factor for developing ED. Diabetes can result in nerve damage to various parts of the body, called neuropathy. Nerve damage in the penis can not only make getting an erection more challenging, but if the damage is severe enough it could result in making an erection impossible. 

Nitric oxide is an important molecule in the erection process as it works as a chemical messenger telling the muscles of the penis to relax and the blood vessels to expand. With diabetes, blood glucose is typically higher than normal or poorly managed, and when this occurs the body produces less nitric oxide. Less nitric oxide in the bloodstream means more rigid muscles and more narrow blood vessels, resulting in a much more difficult erection process. 

Overall, diabetes contributes to endothelial, cardiovascular, and nervous system damage: all not great for the development of ED.

Treatments for Erectile Dysfunction

If you're experiencing erectile dysfunction, you're probably seeking possible treatments. Fortunately, there are quite a few options and most of them are highly effective. While these treatments won’t cure your erectile dysfunction permanently, they offer effective, temporary solutions by providing an erection firm enough for sex. The most effective treatments include:

Prescription Oral Medications

Since hitting the market in 1998, Viagra® has been one of the most popular drugs in the world. These oral tablets include the active ingredient sildenafil, which works to boost blood flow in the penis. The effects last for around four hours after taking it, depending on various factors.

Other popular options include tadalafil (Cialis®) and vardenafil (Levitra®), both of which are PDE5 inhibitors like Viagra. Due to possible interactions with other diabetes medications, consult with a doctor in order to find out if any of these options are safe for you. Medications for high blood pressure or heart conditions, such as nitrates, can have dangerous effects when mixed with erectile dysfunction medications.   

Injections

In the event that oral medications are not an option, a similar treatment is available, albeit with a much different delivery method. For this treatment, medicine called alprostadil is directly injected into the base or side of the penis with a fine needle. 

The effects should last for around an hour, but the medicine works similarly to the oral tablets and help to increase blood flow and relax muscles in the penis. If needles are an issue, alprostadil can come as a suppository. Instead of being injected into the penis, this method of delivery will have you inserting it into the penis via the urethra.

Pumps

One of the less invasive methods for treating erectile dysfunction is by using a vacuum pump. This tool is a long hollow cylinder that comes with a pump that is powered by hand or battery. The process is fairly simple, but it will take some practice to get proficient at it. 

Insert your penis into the tube and use the pump to remove the air in the cylinder. This creates a vacuum in the tube and draws blood into the penis, forming an erection. Once this happens, typically after a few minutes, the user slides a tension band around the base of the penis, trapping the blood inside and maintaining the erection. 

It’s important not to leave the band on for longer than 30 minutes. While it’s helping to maintain the erection, it’s doing so by cutting off blood circulation. Anything longer than 20-30 minutes can have dangerous side effects. 

Implants

The only surgical option on this list is the penis implant. Typically reserved for the more extreme cases of erectile dysfunction, this treatment involves inflatable implants and a reservoir being placed inside the penis along with an inflatable pumping device in the scrotum. In order to achieve an erection, you pump fluid from the reservoir into the inflatable implants. 

When finished with sexual activity, you then use a release valve to drain the fluid back into the reservoir where it will be stored until needed again. Another option for implants, but less popular, is to use rods that create a semi permanent erection. The penis is rigid, and it may be difficult to maneuver through daily life.

The Takeaway: Diabetes is a known risk factor for erectile dysfunction, and it’s not clear whether the common diabetes treatment metformin causes erectile dysfunction. However, metformin does reduce the levels of testosterone in the body, which may contribute to erectile dysfunction.

Erectile dysfunction as a result of diabetes can be frustrating to experience. However, many of the same lifestyle changes that can help to improve diabetes symptoms can also help reduce erectile dysfunction: eating a healthy diet, getting more exercise, cutting back on alcohol, and quitting smoking can be significantly beneficial to both diabetes and erectile dysfunction.

Prescription ED medications can be beneficial too, and Rex MD can help guys order medications like Viagra from the comfort of home. It starts with a short online survey and ends with generic Viagra or another popular ED medication on your doorstep, if approved.

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