Medically reviewed by: Thomas Fischer (Pharmacist). This article has been written according to strict guidelines and medical standards.
Medically reviewed by: Thomas Fischer (Pharmacist)
When it comes to male sexual health, two trademark names tower above the rest. We are, of course, talking about Viagra and Cialis. The primary function of these medications is aimed at combating erectile dysfunction. Forming part of the PDE5 inhibitor group of drugs, these brands are used for the same purpose and mostly share the same side effects. However, there are minor, noticeable differences between the two drugs.
These differences are apparent in the onset time, duration of the drug’s activity, and a few unique side effects. The other main difference between these drugs lies in the molecular structures of their base chemicals. Only by comparing these two drugs, we can establish which medication works best, Viagra or Cialis. This comparison follows below.
Cialis or Viagra - What's The Difference Between Them?
What Is Viagra?
Pfizer developed Sildenafil and made it available to the public in 1998 under the trademark name of ‘Viagra’ (aka The Little Blue Pill). Viagra is commonly prescribed to be taken as needed. It’s a PDE5 inhibitor that acts as a vasodilator. It is mostly used to combat erectile dysfunction (ED) in men. Pulmonary arterial hypertension (PAH) can also be treated with this medication. In men with impotence, the goal of taking this medication is to regain the ability to produce a lasting erection, firm enough for penetration.
When used for PAH, Viagra hinders PDE5 activity. This increases cyclic GMP activity in the lungs resulting in widening the lung’s blood vessels. This process lowers pulmonary blood pressure and improves the function of the heart.
This medication is produced in 100mg, 50mg, and 25mg doses. Viagra is manufactured as a blueish, diamond-shaped pill and is taken by mouth, and typically, it becomes active half an hour to an hour after intake. It will stay active in the patient’s system for about six hours under the right circumstances.
Because of its short period of activity, Viagra is the drug of choice for men that schedule sex dates. Viagra was not designed to produce an erection on its own. Sexual stimulation (arousal) is needed for this to happen.
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What Is Cialis?
Tadalafil, an Eli Lilly medication, was presented to the public in 2003 under the trademark name of ‘Cialis,’ aka ‘The Weekend Drug.’ Depending on the patient’s needs, Cialis can be prescribed to be taken as necessary or as a daily therapy drug. It is most commonly used to counter the symptoms related to impotence in men.
Other uses for this drug include treating benign prostatic hypertrophy (BPH) and Ayerza syndrome (PAH). Like Viagra, Cialis is also a PDE5 inhibitor and acts as a vasodilator. In the treatment of PAH, Cialis decreases PDE5, which increases cGMP activity in the lungs. This causes the lungs’ blood vessels to widen, which reduces pulmonary blood pressure to the heart and improves its function.
In the treatment of BPH, Tadalafil relaxes muscle cells in the prostate and bladder, which results in alleviating the urinary symptoms of BPH.
For many men, Cialis has become the preferred drug. Because of its long duration of effectiveness, it allows for spontaneous sexual encounters. Daily therapy Cialis also relieves impotence in men on a more long term basis, allowing these men to produce an erection on demand. Regardless of how it’s taken, without sexual arousal, Cialis will not cause an erection.
Cialis is manufactured in 5mg, 10mg, and 20mg doses, in a yellow or orange almond-shaped tablet, and is taken by mouth.
For Which Conditions Are Viagra And Cialis Used?
Typically, Viagra is prescribed to relieve the symptoms of impotence in men and PAH treatment. Alternative uses for Viagra include the treatment of:
- Mountain sickness
- Heart disease, and
- Raynaud's phenomenon
Cialis is designed to prevent the symptoms of erectile dysfunction in adult men and for treating BPH and PAH.
Active Ingredients of Cialis & Viagra Compared
The active ingredient used in Viagra is Sildenafil citrate, and Tadalafil is the base chemical of Cialis. Adcirca is also a Tadalafil based drug. Both Tadalafil and SIldenafil are FDA approved drugs and legal to buy in the USA with a doctor’s prescription. Although these drugs are both PDE5 inhibitors and produce a similar outcome, their molecular structures are very different.
- Sildenafil molecular structure - C22H30N6O4S
- Tadalafil molecular structure - C22H19N3O4
Effects Of Viagra vs. Cialis
Although they are different at a molecular level, Viagra and Cialis’s intended effect is the same. Their function is explained below:
- The inability in men to produce an erection, referred to as impotence or erectile dysfunction (ED), stems from an abundance of the PDE5 enzyme in the adult male body.
- The function of these enzymes is to destroy cGMP enzymes (necessary to produce an erection) immediately after ejaculation. In men with impotence, however, the abundance of these enzymes kill the cGMP too soon. This results in one being incapable of producing an erection.
- The function of Viagra and Cialis (PDE5 inhibitors) is to prevent PDE5 from destroying the cGMP prematurely. Allowing the natural role of cGMP to occur and granting men the ability to produce a firm and lasting erection.
The difference between the two drugs lies in the amount of time they take to kick in and how long they remain active in your system. There are some unique side effects related to each drug.
Comparison Of Effects Of Viagra vs. Cialis - Onset Time & Duration
The effect of Viagra and Cialis are the same. These drugs were designed to enable an individual with impotence to have and maintain an erection that is firm enough for sexual intercourse. Both drugs have also proved to be effective in at least 90 percent of patients that have taken the medication. The difference in their effect lies in the time it takes for these drugs to become productive and for how long they remain active.
It takes Viagra, after consumption, between 30 and 60 minutes to become effective in your body. It will retain its efficiency in your system for four to five hours. The duration of activity may be increased to approximately six hours under the right circumstances.
Cialis can take as much as two hours to become active and will remain productive for at least 36 hours. It is for this reason that Cialis is often called ‘The Weekend Pill.’. The onset time of Cialis may be reduced under the right circumstances.
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Dosages Of Viagra & Cialis
No one should use Cialis or Viagra without first consulting a medical practitioner. Your doctor will prescribe either one of the two drugs and supply you with the correct dosage.
Viagra is generally prescribed as a 50mg dose, which is to be taken as needed. The dosage may be decreased to 25mg or increased to 100mg by your doctor depending on your tolerance to the drug and its efficiency on your system.
Cialis can be prescribed for daily use or to be taken as needed. It all depends on your reason for using the drug.
- Your doctor will typically start you on a 2.5mg dose for daily use, which may be increased to 5mg if necessary.
- For use as needed, the physician will generally start you on a 10mg dose. This may be decreased to 5mg or increased to 20mg. It depends on the drug's efficiency in your system and your tolerance to the drug.
Viagra vs. Cialis - Comparing The Side Effects
Because of their similarity, Cialis and Viagra mostly share the matching side effects. Typical side effects of these drugs include:
- Headaches
- Stomach pain
- Facial flushing
- Diarrhea
- Nausea
- VIsion impairment
- Muscle pains
- Priapism, and
- Hypotension
Common side effects are seldom severe and normally works itself out within a couple of hours. If they persist, most doctors recommend lowering the dose. There are, however, some side effects that are unique to each drug.
Side Effects of Viagra
In rare cases, men have experienced Priapism (painful erections lasting over 4 hours). NAION (loss of blood flow to the optic nerve) has also been reported as an adverse effect of Viagra. Other users have reported rashes, UTI (urinary tract infection), and nasal congestion. If one of these undesired effects occur, it should be treated immediately by a medical professional. Untreated Priapism may result in permanent penile damage, and NAION may lead to permanent blindness.
Side Effects of Cialis
In rare instances, Priapism, NAION, blindness, and hearing loss have been reported. Some users also report cases of abnormal ejaculation.
Differences In Interactions - Viagra vs. Cialis
Cialis and Viagra, unless prescribed by a doctor, should not be used in combination. The combined use of these medications may cause an increased quantity of both drugs in your blood system. This increases your chances of experiencing side effects.
Because both medicines act as vasodilators, using them together may also cause sudden severe hypotension (decreased blood pressure). This may lead to heart attacks, renal failure, or strokes, all life-threatening situations. Avoid using either Viagra or Cialis with nitrates, alpha-blockers, antihypertensive (high blood pressure) drugs, and riociguat. An interaction can occur, which may lead to sudden severe hypotension.
Viagra and Cialis may also interact with CYP3A4 inhibitors (such as ritonavir and erythromycin), certain antibiotics, antifungals, and HIV protease inhibitor medication. It may lead to increased Viagra or Cialis levels in your system, which increases your potential for experiencing side effects caused by these drugs.
Certain food types, such as grapefruit and grapefruit juice, should also be avoided. It may raise the levels of Viagra or Cialis in your blood resulting in an increased chance to experience side effects. Alcohol should be controlled and be kept to a minimum when using Viagra or Cialis. It may interfere with the efficiency of these drugs, or result in decreased blood pressure.
Patient Experiences - Viagra vs. Cialis
In various patient testimonies, as well as multiple clinical trials that were conducted, Viagra and Cialis are the most commonly preferred medications for erectile dysfunction. Approximately 90 percent of men are satisfied with the effect that Viagra produces. The most commonly experienced side effects of these drugs are headaches, flushing, muscle pains, and back pain, as reported by these patents.
Several patients have reported that Viagra and Cialis did not only solve their impotence problem, but it also helped them with premature ejaculation issues. According to patient reviews, the medication also allows them to produce a more rigid erection and enables them to last longer during intercourse, fully satisfying their sexual partners.
None of the reviews reported severe side effects such as Priapism or hearing loss. However, serious adverse effects have been reported by clinical trials that have been conducted on both Viagra and Cialis.
Taken from patients reviews, it is clear that a larger percentage of men prefer to use Cialis over Viagra. This is due to Cialis’s long-lasting effect. Its daily therapy use also contributes to this aspect. It enables men with erectile dysfunction the freedom of spontaneity and to produce a firm and lasting erection when the situation calls for it.
Conclusion: Cialis vs. Viagra - Which is right for you?
It is not fair to deem Viagra to be better than Cialis and vice versa. What works for one person does not necessarily mean it will work for the next. Furthermore, people’s lifestyles and preferences are never the same. For this reason, it is suggested that you try both drugs. Men that prefer to plan sexual encounters will most likely prefer using Viagra because of its short onset time and duration of effectiveness.
Spontaneous guys will be better suited to use Cialis. Its longevity aspect takes the planning of sexual encounters out of the equation.
It is suggested that you experiment with both Viagra and Cialis. Only through experience will you be able to isolate the medicine that best works for you and suits your preferences. Of course, no decision should be made without first having a consultation with a licensed medical professional.
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