While they both come from the same family of medications, the differences in how they work makes them very distinct drugs. Let’s compare the chemical ingredients and side effects of each of these popular erectile dysfunction (ED) medications.
What is the Difference Between Chemical in Viagra and Cialis?
Viagra and Cialis are two of the most popular and most well-known ED medications currently available. Both of these drugs work by boosting blood flow to the penis during sexual stimulation. However, their active ingredients are largely different. While both of these medications are chemically classified as PDE-5 inhibitors, which stands for the family of medications that they are in, they function differently. This difference is key, as it determines how each drug is used and how they affect the body. Let’s take a look at what is the difference between chemical in Viagra and Cialis.
Active Ingredient And Effect
The active ingredient in each of these medications is sildenafil. Sildenafil is a phosphodiesterase (PDE) inhibitor, which stops cyclic guanosine monophosphate (cGMP) from being broken down by enzymes. This prevents the smooth muscle cells of the corpora cavernosa from relaxing and allowing blood to flow into the penis during sexual stimulation. As a result, a man is able to achieve an erection. So what is the difference between these two drugs? Well, in terms of the active ingredient, sildenafil is only present in Viagra at therapeutic levels. In terms of their actual effects, Viagra has a much more profound effect than Cialis. This is largely because its sildenafil content is seven times greater than Cialis’s.
Tolerability
The side effects of these medications are also fairly different, which is again due to the different concentrations of active ingredients in each one. When taken at therapeutic levels, sildenafil is generally well-tolerated. However, at higher concentrations, it can be dangerous. The primary side effect of sildenafil is generally similar to that of any other medication in its class. This is extreme lightheadedness or dizziness. Thankfully, this side effect is fairly rare and can be treated with medication or a change in dosage. More commonly, sildenafil has been associated with headache, flushing, and gastrointestinal discomfort. Although these are all relatively common side effects of sildenafil, they are still fairly mild in nature and rarely require discontinuation of the medication. In many ways, sildenafil is a fairly well-tolerated medication. When compared to its relative, Cialis, sildenafil is safer and more commonly used because of its greater tolerability.
Metabolic Effect
One of the more interesting differences between these two medications is the effect that they have on the body. When ingested, sildenafil is quickly transformed into inactive metabolites by the liver. However, due to its vasodilatory effect, sildenafil has a tendency to accumulate in the body. Studies have shown that when sildenafil is administered at therapeutic levels, this accumulation does not occur. In other words, the liver metabolizes sildenafil rapidly enough so that it is not significantly accumulated in the body. When compared to Cialis, which is minimally metabolized upon ingestion, sildenafil has a much longer half-life in the body. As a result, it has a greater tendency to accumulate over time, which is why it should be used only for short-term ED therapy.
Based on the different active ingredients and side effects of these two medications, it’s clear that they serve very distinct purposes. Viagra is a first-line treatment for ED, due to its sildenafil ingredient and greater tolerability. However, as a result of its longer half-life and greater accumulation in the body, Cialis may be a better choice for patients looking for a medication with a more profound effect.