Is Cialis (tadalafil) Safe for Diabetics?

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Erectile dysfunction is common amongst men who have diabetes. The problem stems from damage to blood vessels and nerves, caused by poor sugar control. It is estimated that 75% of diabetic men will experience some form of ED at some point.

This article will examine one popular erectile dysfunction treatment, tadalafil tablets – better known by the brand name Cialis – in order to determine if men suffering from Type I or Type II diabetes, can take the drug to help them achieve an erection.


What is Cialis (tadalafil)?

Commonly sold under the brand name Cialis, tadalafil is one of the more popular treatments for erectile dysfunction. Tadalafil is a drug that belongs to the class of medication, known as PDE-5 inhibitors and is often referred to as ‘generic Cialis.’ A relatively newer impotence treatment, tadalafil does not increase libido, and will only work in situations where sexual stimulation occurs. This oral medication can be used safely by diabetics.

Cialis is available in a 10mg and 20mg strength, that is taken 30 minutes before sexual activity. The effects can last for up to 36 hours. Cialis is also available in lower strength of 2.5mg and 5mg. The lower dose means that you can take tadalafil daily, in order to build up a constant low dose of Cialis in the body. This allows men to achieve and maintain an erection spontaneously, without the need for scheduling doses 30 minutes before sex. This tablet is commonly referred to as, Cialis daily, or tadalafil daily.

How does Cialis work?

Cialis works in similar ways to other popular erectile function medications, such as Viagra. When you’re sexually stimulated, your nervous system releases nitrous oxide, which acts as a vasodilator, relaxing blood vessels and allowing oxygen and other nutrients to pass through the body. 

The release of nitrous oxide triggers the production of a messenger called cGMP, which causes blood to flow freely to your penis, resulting in an erection. For men suffering from ED, the PDE-5 enzyme causes the breakdown of cGMP, so that the ability to achieve an erection is prevented.

Cialis, like many popular ED pill treatments, blocks PDE-5 so that it cannot break down cGMP. This allows blood to freely flow to your penis, resulting in an erection in the event of sexual arousal.


Is Cialis good for people with diabetes?

Men with diabetes who are considering the use of Cialis can rest assured that the medication is generally safe, although there are some recommendations and guidelines they should consider before beginning treatment.

As a general rule, you shouldn’t use Cialis or any other ED drugs if your blood sugar levels are out of control, or even temporarily unregulated. Even though tadalafil’s mechanism of action is unlikely to affect sugar levels, some studies suggest that men with unregulated blood sugar levels could be more prone to significant adverse reactions to Cialis, as opposed to patients with regulated blood sugar levels.

If your diabetes is under control, Cialis has been proven to be safe and well tolerated according to studies. Another study demonstrated that tadalafil significantly improved diabetic patient’s ED, in over two thirds of diabetic men.

Before taking Cialis – or while taking new prescription medication that may interact with other treatments, it is wise to consult your physician or health care provider. Your doctor may have insight as to how combining tadalafil with diabetes medications has worked from experiences shared by other patients. At the very least, they will be familiar with your overall health and medical history and can provide some additional information or insight as to how Cialis may work for you.


Can I take Cialis if I’m also taking nitrate medications?

Nitrate-containing drugs are the one class of medications this ED treatment should never be mixed with.  Even if you rarely use nitrate medications, you should not take Cialis since you can never really be sure when you’ll need to use nitrate therapy. Concomitant use of nitrates and Cialis can cause your blood-pressure levels to drop to life-threatening levels. 

Some of these nitrate-containing drugs include:

  • Glyceryl trinitrate tablets, spray or patches
  • Isosorbide dinitrate (Isordil)
  • Isosorbide mononitrate (Imdur)
  • Amyl nitrite “poppers”


What about Cialis with other diabetes medication?

Cialis does not interact with insulin; nor does in interact with metformin or gliclazide, two commonly used treatments in the management of type 2 diabetes.

However, tadalafil may interact with SGL2 inhibitors, such as dapagliflozin, canagliflozin, and empagliflozin. Taking tadalafil with these medications can cause a slight drop in blood pressure, which can cause dizziness and headaches. If you are taking any of the ‘gliflozin drugs’, your doctor or pharmacist is likely to start you on the lower doses of tadalafil, to minimize the risk of side effects. Many men, especially those who have acquired type 2 diabetes, are likely to also be taking medication to treat hypertension. Tadalafil interacts with most antihypertensives, having the potential to lower blood pressure. If you are taking antihypertensives, your doctor or pharmacist is likely to start you on a lower dose of tadalafil, to help minimize the chances of side effects.


What are the side effects of Cialis for people with diabetes?

Cialis is not likely to cause side effects that are more pronounced in people with diabetes. Side effects have the potential to affect diabetics, in the same way they affect non-diabetics.

Some reported side effects include headache, facial flushing, nasal congestion, and heartburn. If you experience an adverse event, such as a painful or prolonged erection that lasts for over four hours, seek medical attention.

If you’re experiencing a loss of sex drive, or the inability to achieve an erection hard enough for sexual intercourse, consult a medical professional or healthcare provider, to determine whether your condition is being caused by an underlying health concern. 

Whilst men with diabetes are around three times more likely to experience ED, there are treatments such as Cialis, that are safe and effective.

Whilst all of our content is written and reviewed by healthcare professionals, it is not intended to be substituted for or used as medical advice. If you have any questions or concerns about your health, please speak to your doctor.



How common is erectile dysfunction?

It is estimated that around 4 million men in the UK suffer with some form of ED, with issues such as diabetes and heart disease accounting for around 70% of ED cases. If you have noticed ED getting progressively worse, you should see your doctor. There may be an underlying health condition that could be the cause.

Can diabetic erectile dysfunction be cured?

The only way that ED caused by diabetes can be reversed or cured, is by controlling your blood sugar levels. Unfortunately, for type 1 diabetics, this may not be an option. If you are a borderline type 2 diabetic, blood vessels and nerves may not have sustained prolonged damage, which means that there may be a possibility to reverse diabetes induced ED. However, this does depend on the extent of damage that uncontrolled blood sugar levels have caused.

Will lowering blood sugar help ED?

Controlling blood sugar levels will help prevent nerve damage and damage to blood vessels, both of which contribute to ED.

Whilst all of our content is written and reviewed by healthcare professionals, it is not intended to be substituted for or used as medical advice. If you have any questions or concerns about your health, please speak to your doctor.