Tadalafil (CIALIS) vs Sildenafil (Viagra) – Is One Better?

Comparing Tadalafil (Generic Cialis) and Sildenafil (Generic Viagra)

Man choosing between generic medications for erectile dysfunction

When patients approach our pharmacy seeking effective relief from erectile dysfunction, they often find themselves grappling with the decision of which medication to choose: tadalafil or sildenafil. In the past, when these medications were still under patent protection and marketed under the brand names Cialis and Viagra, respectively, prices were exorbitant, leading to numerous challenges with insurance companies. Fortunately, the landscape has dramatically changed with the introduction of generics, making these highly effective drugs far more accessible to a broader audience. We typically recommend that patients who are new to ED treatments consider trialing both medications separately to determine which one not only works best for them but also carries the fewest side effects. Given the current competitive pricing, the financial risks associated with experimenting to find the most suitable option for a patient's specific needs are minimal.

Comparing the Mechanism of Action

Dr. Engel Seminar PromoWhen we delve into the pharmacological mechanisms of sildenafil and tadalafil, it becomes evident that both medications share a common approach as phosphodiesterase type 5 (PDE-5) inhibitors. This specific action inhibits the degradation of cyclic guanosine monophosphate (cGMP), a crucial molecule that facilitates the relaxation of smooth muscles and enhances blood flow to the penis during sexual arousal. It's essential to make it clear that these medications will not amplify sexual desire; rather, they are designed to improve the physiological response, enabling the penis to engorge with blood, resulting in a satisfactory erection. However, it's important for patients to keep in mind that these medications do not guarantee success in every instance and that outcomes can vary significantly depending on the underlying severity of erectile dysfunction. As erectile dysfunction progresses, patients may find it necessary to adjust their dosages. Ultimately, it’s common for individuals who initially respond well to these medications to experience a decline in effectiveness over time, leading to the need for additional therapeutic interventions.

Comparing Which Works Faster

Both tadalafil and sildenafil typically take about 30 to 60 minutes to begin exerting their effects, allowing patients the opportunity to achieve the desired erection. However, peak plasma concentrations differ slightly: tadalafil reaches its peak around two hours post-ingestion, while sildenafil does so about one hour after consumption. Therefore, we often advise patients to take their chosen medication approximately one to two hours before engaging in sexual intimacy. It’s worth noting that the onset time can differ among individuals, so it's beneficial to use previous experiences as a reference when determining the optimum timing for administration.

Interestingly, sildenafil's absorption can be significantly impaired if taken after a large meal that is high in fats, an issue that does not affect tadalafil. For this reason, sildenafil may be more suited for couples with a stable and predictable sexual schedule, such as married partners, while tadalafil might be the better choice for those who are actively dating, as the more substantial meals typically associated with early dating scenarios can hinder sildenafil’s effectiveness.

Comparing Which Lasts Longer

When it comes to the duration of action, tadalafil clearly outshines sildenafil. Sildenafil remains effective for approximately four to six hours post-dosage, while tadalafil can provide the ability to maintain erections for up to 36 hours after intake. This prolonged effect is particularly beneficial for younger men or those experiencing milder forms of erectile dysfunction. In both cases, it’s crucial to remember that neither medication enhances sexual desire; they simply enhance the quality of an erection when the desire is present and appropriate.

Comparing Side Effects

As with any pharmacological treatment, it is essential to consider the potential side effects associated with both sildenafil and tadalafil. In general, both medications are well tolerated among the majority of patients; however, some individuals may experience adverse effects.

Common side effects reported by patients taking sildenafil include mild headaches, feelings of nausea, flushing of the skin, stuffy nasal passages, and, on occasions, indigestion or dizziness. Some patients have also reported a bluish tint to their vision. Generally, these side effects are temporary and resolve after discontinuation of the medication. In very rare cases, sildenafil has been associated with serious side effects like sudden loss of vision, which necessitates immediate medical intervention due to the potential risk of permanent blindness. Patients with pre-existing eye conditions, cardiovascular diseases, or metabolic disorders such as high cholesterol, hypertension, or type 2 diabetes may find themselves at a heightened risk.

In contrast, tadalafil presents a different spectrum of side effects. While it shares common side effects such as headaches, indigestion, and nasal congestion with sildenafil, tadalafil may also induce unique symptoms like lower back pain, cough, and respiratory infections. Notably, research has suggested that both medications, despite their side effect profiles, may contribute to a reduction in the risk of mortality related to cardiovascular disease by as much as 25%. It’s critical to recognize that this does not imply either medication serves as a treatment for heart disease, nor does it replace any current cardiovascular therapies.

Both sildenafil and tadalafil maintain a relatively low risk profile, but it’s important to be aware that any side effects associated with tadalafil may last longer due to its extended half-life compared to sildenafil.

Comparing Drug Interactions

If you have previously received a prescription for erectile dysfunction medication or are considering one now, your healthcare provider will likely inquire about any other medications you might be taking, particularly nitrates. Nitrates, such as nitroglycerin, have the potential to cause a significant drop in blood pressure, which can lead to life-threatening complications like heart attack or stroke. Patients who utilize nitroglycerin often possess serious cardiovascular conditions that already put them at higher risk, making the concurrent use of ED medications particularly dangerous. Similarly, recreational substances known as “poppers,” which include amyl nitrate, amyl nitrite, and butyl nitrate, should never be combined with ED medications. It is critical to consult your healthcare provider or pharmacist regarding any potential drug interactions to ensure safe usage of ED treatments.

Does Either Medication Reverse ED?

Dr. Engel often likens erectile dysfunction to a roller coaster ride. The journey toward ED is generally gradual, yet once it disrupts sexual activities, it usually leads to a steady decline that is difficult to reverse. While erectile dysfunction medications, such as sildenafil and tadalafil, can temporarily enhance blood flow to the penis, thereby improving the erectile response, the underlying vascular problems associated with ED typically intensify with age, and unfortunately, there is no remedy for this natural progression. Consequently, over time, these medications may become less effective, leading healthcare providers to explore additional treatment methods, including penile injections or prosthetic implants.

Which Makes You Harder?

While both sildenafil and tadalafil yield comparable quality of erections, studies indicate that a slightly larger number of men report achieving satisfactory erections with sildenafil.¹ However, as previously mentioned, tadalafil's extended presence in the bloodstream leads to its preference among many men, likely because of the flexibility it provides in intimate situations without the pressure to time sexual activity precisely.

The Bottom Line

In light of the affordable generic pricing that exists for both medications, Dr. Engel firmly believes that there should not be a one-size-fits-all approach to prescribing erectile dysfunction medications. As outlined earlier, each drug carries its unique benefits and risk profiles, which should be thoroughly discussed during a healthcare consultation. Given the current market prices, most patients are in a position to safely trial both sildenafil and tadalafil to identify which option best suits their individual needs. Of course, if any side effects occur with either medication, it is advisable to halt usage and consider switching to the alternative. If side effects prove to be severe or persistent, immediate medical attention should be sought.

Reference:

1Doggrell SA. Comparison of clinical trials with sildenafil, vardenafil, and tadalafil in erectile dysfunction. Expert Opin Pharmacother. 2005 Jan;6(1):75-84. doi: 10.1517/14656566.6.1.75. PMID: 15709885.