Cialis 20 mg: Uses, Benefits, Side Effects & More

You might have seen Cialis® — the erectile dysfunction (ED) drug — available in doses ranging from 2.5 mg to 20 mg. Surely, more is better right?

Well, not always. Cialis 20 mg is an effective erectile dysfunction treatment, but so are the lower doses.

Below, we’ve covered what Cialis 20 mg is used for, the benefits and side effects of this dose of Cialis, and how it stands up against other strengths.

Cialis is the brand name for tadalafil, which is classified as a phosphodiesterase type 5 inhibitor (PDE5 inhibitor). This means it plays a crucial role in managing blood flow in the body.

Cialis is FDA-approved to treat:

• Erectile dysfunction

• Benign prostatic hyperplasia (BPH), or an enlarged prostate

Cialis dosages include 2.5 mg, 5 mg, 10 mg, and 20 mg.

You have the option to take Cialis as needed before sexual activity or on a daily basis to maintain readiness.

If it’s taken as needed, you’ll likely be prescribed 5mg, 10mg, or 20mg, with 10mg being the typical starting point, which can be adjusted based on how it's working for you and any side effects you might experience.

However, daily use of Cialis typically involves the lower doses of 2.5 mg and 5 mg to avoid complications associated with higher doses.

How does Cialis work? For ED, which is when you struggle to achieve or maintain an erection, Cialis facilitates the dilation of blood vessels in the penis. This leads to an enhanced blood flow, resulting in a firmer erection.

It’s essential to understand that Cialis, whether 20 mg or not, does not simply induce an erection; sexual arousal is still necessary for it to function effectively.

Cialis 20 mg may serve as a more potent option for ED compared to the 10 mg version. Clinical studies have shown that between 68% to 77% of men taking 10 mg Cialis successfully managed penetrative sex. In contrast, those on 20 mg saw success rates between 76% and 85%.

However, not all research corroborates this — some studies indicate that lower daily doses can be just as effective as the as-needed Cialis treatment.

An extensive systematic review evaluated six randomized controlled trials involving over 1,500 participants and discovered that both the as-needed tadalafil treatment and the once-a-day regimen yielded similar effectiveness.

Tadalafil is also utilized for treating pulmonary arterial hypertension, which is a condition characterized by high blood pressure affecting lung blood vessels.

A 20 mg dose can prove beneficial in this context as well. A 2006 study showed that a single dose of 20 mg tadalafil led to a reduction in average blood pressure for 26 hours among patients suffering from uncontrolled hypertension.

For further information, be sure to check out our comprehensive guide on tadalafil uses.

Some notable Cialis benefits include:

• Extended duration of action. Cialis lasts significantly longer than alternatives like Viagra, earning it the moniker “the weekend pill.” Just one tablet can provide effects lasting up to 36 hours, allowing for spontaneity in intimate encounters. In contrast, avanafil lasts just up to six hours and Viagra® has a window of up to four hours.

• Proven effectiveness. Clinical data highlights that Cialis is effective across various severities of ED, including more challenging cases. If the 10 mg dose of Cialis isn’t delivering the results you seek, the 20 mg strength could be your solution.

• No daily commitment. Depending on your habits and preferences, you may prefer not to take medication every single day. The 20mg dosage is intended for as-needed use, rather than a daily regimen.

• Generally mild side effects. The adverse effects associated with Cialis tend to be mild and transient — although these might be more noticeable at higher doses. For instance, around 11% of participants on 10 mg tadalafil reported headaches, while this increased to 15% for those on 20 mg.
  Side effects like flushing and limb pain occur at similar rates for both doses. Should side effects become bothersome while taking Cialis 20 mg, consultation with a healthcare provider can help identify possible solutions including dosage adjustment.

• Reduced flushing. If flushing becomes a troublesome effect while taking ED medications, transitioning to Cialis might be a suitable alternative. A 2017 systematic review and meta-analysis comparing sildenafil (the main ingredient in Viagra) and tadalafil discovered that tadalafil resulted in lower incidences of flushing.
  While muscle aches and back pain were reported more frequently with tadalafil compared to sildenafil, overall both medications demonstrated comparable efficacy and safety profiles, with many individuals preferring tadalafil for its tolerability. For additional insights, explore our Cialis vs. Viagra comparison.

Despite its benefits, Cialis carries certain potential side effects.

The most prevalent Cialis side effects include:

• Headache

• Dyspepsia (indigestion)

• Back pain

• Myalgia (muscle aches)

• Nasal congestion

• Flushing

• Limb pain

These effects can occur in as few as three percent of those taking Cialis 10 mg or 20 mg.  

Clinical assessments indicate that side effects are dose-dependent, meaning they’re more likely with higher dosages — thus, the likelihood of experiencing side effects increases with 20 mg Cialis.

An allergic reaction, although uncommon, is still a possibility with Cialis, which may manifest as:

• Rash

• Hives

• Swelling of the lips, tongue, or throat

• Difficulties in breathing or swallowing

Additionally, there’s a risk of priapism, which is characterized by prolonged erections lasting several hours. While this might seem appealing initially to those experiencing ED, prolonged erections can lead to pain and may cause irreversible damage to the penis.

If an erection persists beyond four hours, it’s crucial to seek immediate medical assistance. Certain conditions, including the following, may increase the likelihood of prolonged erections:

• Sickle cell anemia

• Multiple myeloma

• Leukemia

• Anatomic deformations in the penis (for instance, Peyronie’s disease)

For more information on priapism and what steps to take if you think you are affected, consult our guide.

There is a slight chance of experiencing vision loss, which should prompt immediate discontinuation of Cialis and medical evaluation. This could indicate a condition known as non-arteritic anterior ischemic optic neuropathy (NAION), which results from compromised blood flow to the optic nerve.

A sudden drop in hearing or hearing loss is another serious concern. If you notice such changes, seeking medical advice promptly is critical.

Several drug interactions warrant caution when taking Cialis.

The combination of Cialis and nitrates is strictly contraindicated, as it can lead to a dangerous drop in blood pressure, resulting in dizziness, fainting, or potentially serious cardiovascular events like heart attack or stroke. Medications containing nitrates include isosorbide dinitrate or isosorbide mononitrate.

Be wary of recreational substances that may contain nitrates, commonly known as “poppers.” Additionally, individuals taking guanylate cyclase stimulators, such as riociguat, should avoid Cialis altogether.

For those on alpha-blockers (like doxazosin or tamsulosin) or CYP3A4 inhibitors (like erythromycin or ketoconazole), a lower Cialis dose may be recommended.

The safety of combining Cialis with other PDE5 inhibitors, such as:

• Viagra (sildenafil)

• Levitra® (vardenafil)

• Stendra® (avanafil)

is still uncertain. Always inform your healthcare provider about any medications or supplements you currently take before starting Cialis therapy.

Alcohol intake should also be moderated while taking Cialis.

Excessive consumption (five units or more) may elevate the risk of experiencing:

• Increased heart rate

• Decreased standing blood pressure

• Dizziness

• Headache

Interestingly, grapefruit and Cialis interact in ways that should be noted. A 2020 study discovered that grapefruit juice inhibits the metabolism of tadalafil, which can lead to an increased concentration of tadalafil in your system and subsequently raise the risk of side effects.

For more information on dietary interactions, refer to our guide on tadalafil interactions.

No matter your situation, discussing any medical conditions with your healthcare provider before considering Cialis is vital to ensure its safety.

This includes, but is not limited to:

• Heart conditions like angina (chest pain due to reduced blood flow to the heart)

• Low blood pressure

• Stomach ulcers

• Retinitis pigmentosa (a hereditary eye disorder)

Cialis is available in various dosages, each with specific indications:

• Cialis 2.5 mg. For those on a daily regimen, the starting dose may be 2.5 mg, which can be increased to 5 mg if needed.

• Cialis 5 mg. This dosage is often prescribed for managing BPH. If you have both ED and BPH — two conditions that frequently occur together — a 5 mg daily dose of Cialis might be suitable.

• Cialis 10 mg. When using Cialis as an on-demand treatment for ED, the 10 mg dose is typically the starting point. A healthcare provider can adjust the dose to either 20 mg or down to 5 mg based on response and tolerability.

• Cialis 20 mg. This higher dosage is generally reserved for individuals who have previously tried and found 10 mg insufficient for their needs.

Each tadalafil dosage presents its unique set of advantages and disadvantages, whether you're opting for 20mg Cialis or a lower strength. The recommended daily dosage usually starts at 2.5mg and can be adjusted accordingly.

Taking a smaller daily Cialis dose allows for immediate readiness, but it requires consistency and can lead to lingering side effects. In contrast, the benefit of a higher-dose treatment as needed is that you don’t have to take it every day, reducing the risk of missed doses, and higher doses typically offer greater efficacy. However, greater doses also carry a higher likelihood of side effects.

Consulting with a healthcare professional is essential for determining the most suitable Cialis dosage tailored to your needs.

Just so you know: Cialis is not available over the counter. A prescription from a healthcare provider is necessary to obtain it, but telehealth options may allow you to receive Cialis without leaving your home.

Be cautious with any non-prescription substitutes for Cialis, as they lack FDA approval and may harbor unsafe contaminants.

Many have been reported to contain anywhere from negligible to over 200 percent of their labeled active ingredients, posing significant health threats.

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