What Is Viagra?
Viagra is the name brand of the generic medication sildenafil citrate. It was first patented as a heart medication for angina, but early clinical studies showed that it was not adequate for that use. The studies also showed that it had a side effect – increased numbers of erections in men. Viagra is “the little blue” pill that is used as a treatment for erectile dysfunction. Viagra is the first medication produced for that treatment.
Viagra is taken on an “as needed” basis when the patient wants to have sexual activity. It is available as 25 mg tablets, 50 mg tablets, and 100 mg tablets to be taken by mouth.
What Does Viagra Treat?
Viagra is prescribed to treat erectile dysfunction.
What Is Erectile Dysfunction?
Erectile dysfunction, or impotence, is the inability to be able to get and also keep an erection. Erectile dysfunction is a fairly common occurrence in aging men and may be related to prostate enlargement or falling testosterone levels.
Symptoms of erectile dysfunction include:
- Difficulty getting an erection
- Difficulty keeping an erection
- Decrease in sexual desire
How Does Viagra Work To Treat Erectile Dysfunction?
Viagra is one member of a class of medications known as PDE5 inhibitors. It and other members of the class work to help create erection in men by acting as a vasodilator to increase blood flow to the penis. Blood engorgement of the penis is necessary for the development of an erection.
What Company Manufactures Viagra?
Viagra is manufactured by the pharmaceutical giant Pfizer. It quickly gained notoriety and is still the top-selling prescription medication produced by Pfizer. Within the first weeks after approval, more than 40 thousand prescriptions had already been filled. It was featured the same year in both Time and Newsweek magazines and discussed on Larry King Live.
Pfizer hired Bob Dole, former US Senator and Presidential nominee as a spokesperson and coined the term “ED” to address the reason for using the medication. Viagra became so popular that it was featured in the hit television show “Sex and the City”.
In Viagra’s peak sales year of 2012, revenue from Viagra was reported at over $2 billion with about 8 million prescriptions written. More than 45 million men have used Viagra since it hit the market.
Is Viagra FDA-Approved?
Viagra received FDA approval in 1998.
In 2000, reports began to surface that hundreds of patients may have died while taking Viagra in the first year it was on the market. Despite cardiology concerns, the Food and Drug Administration (FDA) approved Levitra and Cialis for the same indication by 2003.
In 2005, a consumer advocacy group requested that the FDA require a black-box warning be added to Viagra and other impotence medications regarding an increase in incidences of blindness after 48 patients had reported cases of non-arteritic ischemic optic neuropathy (NAION) between 1998 and 2004. Less severe warnings had already been added but a black box was not added.
What FDA Warnings Are There for Viagra?
In October of 2007, Viagra labeling was modified to include warnings about sudden hearing loss after the FDA had received 29 reports regarding patients who had sudden hearing loss within a short period of time of taking the medication. In 2008, Viagra and other ED medications had warnings regarding amnesia or temporary memory loss added to labeling.
In April of 2014, a study published in the Journal of the American Medical Association (JAMA) showed that data from over 25 thousand men taking Viagra indicated that men taking Viagra had an 84% increased risk of developing melanoma, one of the deadliest forms of cancer. Men who had previously taken Viagra continued to be at risk even when the drug was discontinued.
Does Pfizer Still Have a Patent for Viagra?
Viagra was set to go off-patent in 2009 but received a patent extension to prohibit generic medication from entering the market. Viagra’s patent was set to expire in 2020. In December 2020, companies making generic forms of Viagra were allowed to enter their products into the market. Pfizer itself released a generic form of Viagra, as did at least two other companies.
Does Viagra Cause Side Effects?
Viagra, like almost all medications, can cause a number of side effects. Many of the side effects of Viagra are mild, but some are more severe and can become life-threatening.
What Are Mild Side Effects of Viagra?
Viagra can cause a number of side effects that occur because of its vasodilation effects.
Common side effects may include:
- Headache
- Flushing
- Indigestion
- Nasal congestion
- Urinary Tract Infection
- Dizziness
- Back Pain
- Changes in heart rate and blood pressure
- Priapism (extended erection which may cause permanent damage to penile tissue)
What Are Serious Side Effects of Viagra?
Some side effects of Viagra may be severe, and in some cases, permanent or life-threatening. Viagra can have serious effects on the heart, hearing, and vision. Viagra has also been shown to increase the risk of melanoma.
How Does Viagra Affect the Heart?
Viagra has been suspected of causing heart complications in patients who have taken the medication, even if for a short period of time. Viagra is a vasodilator and was initially developed for the treatment of angina, a heart condition causing chest pain.
Side effects of Viagra that are related to the heart may include:
- Angina
- EKG changes
- Rapid heart rate
- Drop in blood pressure causing dizziness
- Heart failure
- Heart attack
It was reported as early as 2000 that Viagra may have contributed to the deaths of nearly 500 men in the first year that it was on the market. These reports have not been linked directly to Viagra but any heart symptoms should be reported to a physician immediately.
How Does Viagra Affect Hearing?
Viagra has been known to cause a sudden loss of hearing, shortly after taking the medication or within a few days. It may cause hearing loss due to its vasodilation effects. It may also cause changes in blood supply in certain areas of the brain that may contribute to tinnitus, hearing loss, and migraine headaches. Most of these types of effects are temporary but should be reported to a medical professional.
How Does Viagra Affect Vision?
Viagra has been known to cause a number of side effects related to the eyes and vision.
Less severe side effects may include:
- Irritation
- Dilation of the pupils
- Photophobia or light sensitivity
- Dry eyes
- Eye pain
More severe effects include multiple reports of non-arteritic ischemic optic neuropathy (NAION) which may cause blindness. This is a permanent change to the optic nerve due to swelling of the tissue surrounding the eye. The condition does not go away after discontinuing the medication in most cases.
Does Viagra Interact With Other Drugs?
Like most medications, Viagra may interact with certain medications. Most of the drug interactions are not severe.
Medications that Viagra may interact with include:
- Medications that are metabolized by the liver such as Tagamet, Erythromycin, and HIV medications (increases Viagra concentrations)
- Prostate medications such as Cardura or Flomax (decreased blood pressure)
- Blood pressure medications such as Minipress, Vasoflex, or Hytrin (decreased blood pressure)
Does Viagra Cause Cancer?
Since entering the market, Viagra has been linked with serious health concerns. Recent reports show that Viagra may double the risk for melanoma, a skin cancer that can lead to fatality.
Melanoma only accounts for 2 percent of skin cancer cases each year but makes up a majority of skin cancer deaths. A recent study by the American Cancer Society estimates about 9,700 people are expected to die of melanoma skin cancer this year; 6,400 of them being men.
Does Viagra Increase the Risk for Melanoma?
A study published in the April 2014 edition of the Journal of the American Medical Association (JAMA) reported that data examined from nearly 26 thousand men showed that those who were taking Viagra and those who had previously taken the medication were nearly twice as likely to get the skin cancer, melanoma.
Viagra may use the same genetic pathways that allow Melanoma to develop but it does not increase the risk of other, less harmful skin cancers such as basal cell or squamous cell carcinoma. Melanoma has an overall 90% survival rate but the survival rate drops to about 16% if not caught in the early stages.
Are There Viagra Lawsuits?
A number of lawsuits have been filed against Pfizer, the manufacturer of Viagra due to the serious side effects of the medication.
Complaints about the medication have included:
- Sudden loss of vision or significant visual impairment
- Sudden loss of hearing or occurrence of tinnitus (ringing of the ears)
- Heart complications that may cause fainting, heart attack, or stroke
- Skin cancer development leading to severe illness or death
Attorneys for the plaintiffs may argue:
- that the manufacturer failed to adequately warn the medical community and the public regarding the risks of Viagra, and
- that the company was irresponsible in its widespread promotion of Viagra leading to severe illness, permanent injury, or death.
Are There Viagra Lawsuit Settlements?
Thousands of lawsuits have been filed in state and federal courts against Pfizer regarding Viagra’s increase in risk for melanoma. Some lawsuits have been dismissed, while others may have been settled.
Notwithstanding claims relating to this product, the drug/medical device remains approved by the U.S. FDA.
Sources
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