Pharmacologic class (EPC) · 7 drug pages

Phosphodiesterase 5 inhibitor: adverse event reports filed with FDA

92,849 reports list a drug in this class as a suspect or interacting product, 2004–2026.

Read first · FDA's statement on these data

Adverse event reports submitted to FDA do not undergo extensive validation or verification. Therefore, a causal relationship cannot be established between product and reactions listed in a report. While a suspected relationship may exist, it is not medically validated and should not be the sole source of information for clinical decision making or other assumptions about the safety or efficacy of a product. Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product. openFDA, FDA

FDA adds: "There is no certainty that the reported event (adverse event or medication error) was actually due to the product. FDA does not require that a causal relationship between a product and event be proven, and reports do not always contain enough detail to properly evaluate an event." The information in these reports "cannot be used to estimate the incidence of these events."

Do not rely on openFDA to make decisions regarding medical care. While we make every effort to ensure that data is accurate, you should assume all results are unvalidated.

Not medical advice. This site counts what was reported to FDA. Questions about a medicine or device belong with a pharmacist or clinician.

92,849
reports across the class: 0.5% of all reports; 3,311
reports, 12 months to June 2026: 3,307 in the 12 months before; 60.1%
marked serious by the reporter: 57.4% across all reports; 7
drugs with a page: brand and generic names counted separately

Phosphodiesterase 5 inhibitor is a pharmacologic class (an FDA Established Pharmacologic Class) with 7 drug pages on this site. Together those drugs are listed as a suspect or interacting product in 92,849 adverse event reports received by FDA, 0.5% of the database, from January 2004 to June 2026.

3,311 reports arrived in the 12 months to June 2026, close to the 3,307 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. 60.1% of the class's reports are marked serious, 12.9% record death among the outcomes and 22.8% record hospitalisation, as reported.

Across the class the reactions recorded most often are drug ineffective (16.5%), headache (7.6%) and death (6.6%). The class median share shown beside each term is the middle value across the member drugs; it is the comparison used on every drug page in this class.

The members table is ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Drugs in the class

Drug	Name type	Reports	Latest 12 months	Marked serious	Top term recorded
ViagraSildenafil citrate	brand	28,349	44	46%	Drug ineffective
CialisTadalafil	brand	15,166	81	35.6%	Drug ineffective
AdcircaTadalafil	brand	12,214	294	66.7%	Headache
Sildenafil	generic	10,726	1,014	82.6%	Drug ineffective
Tadalafil	generic	10,660	1,519	76.1%	Dyspnoea
RevatioSildenafil citrate	brand	9,801	77	83%	Death
Sildenafil citrate	generic	5,933	282	69.1%	Drug ineffective

Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Reports by month, five years

FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

Reactions recorded across the class

share of class reports recording the termmedian drug in the class

Drug ineffectivethe medicine did not work as expected16.5%15,364
Headachehead pain7.6%7,069
Deaththe patient died; cause not stated by this term6.6%6,163
Dyspnoeashortness of breath6.2%5,714
Erection increased3.4%3,147
Dizzinesslight-headedness or unsteadiness3.2%3,005
Off label useused for a purpose or in a way not on the label3.1%2,871
Diarrhoealoose or frequent stools3%2,766
Nauseafeeling sick2.9%2,665
Malaisegeneral feeling of being unwell2.5%2,365
Fatiguetiredness2.5%2,354
Hypotensionlow blood pressure2.3%2,163
Flushingsudden reddening or warmth of the skin2.3%2,117
Malignant melanomamelanoma, a skin cancer2.2%2,019
Pneumonialung infection2.1%1,966
Astheniaweakness or lack of energy2%1,882
Back painback pain2%1,865
Hypertensionhigh blood pressure1.9%1,778
Vision blurredblurred vision1.9%1,732
Coughcough1.8%1,688
Nasal congestiona blocked nose1.8%1,648
Pain in extremitypain in an arm or leg1.8%1,644
Painpain, site not specified1.8%1,643
Condition aggravatedthe condition being treated got worse1.7%1,546
Vomitingbeing sick1.6%1,501

Solid bar: share of all class reports. Hollow bar: the median share across the 7 member drugs, the reference used on each member's page. One report can record several terms.

Outcomes, patients and reporters

Outcomes recorded

Death12.9%12,020

Life-threatening2.2%2,006

Hospitalisation (initial or prolonged)22.8%21,159

Disability1.6%1,495

Congenital anomaly0.1%97

Other serious37.8%35,069

Not serious39.9%37,041

Patient age

Under 20.7%605

2 to 110.8%768

12 to 170.6%570

18 to 448.4%7,784

45 to 6424.3%22,588

65 to 7413.6%12,620

75 and over9.7%9,041

Age not given41.9%38,873

Who reported

Physician13.6%12,659

Pharmacist4.9%4,508

Other health professional17.4%16,198

Lawyer2.9%2,735

Consumer or non-health professional56.3%52,319

Not given4.8%4,430

Grey bar: all 20,646,523 reports in the database. Outcome flags are as the reporter set them and are not verified by FDA.

Questions about Phosphodiesterase 5 inhibitor reports

Which drugs are in the Phosphodiesterase 5 inhibitor class on this site?

Viagra, Cialis, Adcirca, Sildenafil, Tadalafil and Revatio and 1 more. Class membership comes from the pharmacologic class (EPC) on the drug's FDA label.

How many reports does the class have?

92,849 reports through June 2026, 3,311 of them in the latest 12 months. A report listing two drugs of the class counts once for each.

What reactions are recorded most often?

drug ineffective (16.5%), headache (7.6%), death (6.6%), dyspnoea (6.2%) and erection increased (3.4%).

Can the members table be used to rank the drugs?

No. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." Drugs differ in how many people take them, in the conditions they treat, in time on the market and in how diligently reports are collected.

How do I report an adverse event?

Through FDA MedWatch (Form FDA 3500, or 1-800-FDA-1088) or to the manufacturer. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A class is the Established Pharmacologic Class most often attached to a drug's reports by openFDA's label harmonisation, or from the NDC Directory where reports carry none. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.