Sildenafil Side Effects

Medically reviewed by Drugs.com. Last updated on Jun 13, 2023.

Applies to sildenafil: oral powder for suspension, oral suspension, oral tablet.

Other dosage forms:

• intravenous solution

Precautions

It is important that you tell all of your doctors that you take sildenafil. If you need emergency medical care for a heart problem, it is important that your doctor knows when you last took sildenafil.

Do not use this medicine if you are also using a nitrate medicine, often used to treat angina or high blood pressure. Nitrate medicines include nitroglycerin, isosorbide, Imdur®, Nitro-Bid®, Nitro-Dur®, Nitrol® ointment, Nitrolingual® spray, Nitrostat®, and Transderm Nitro®. Some illegal ("street") drugs called "poppers" (such as amyl nitrate, butyl nitrate, or nitrite). Do not use this medicine if you also use riociguat (Adempas®).

If you will be taking this medicine for pulmonary arterial hypertension, your doctor will want to check your progress at regular visits. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to take it.

If you take sildenafil for pulmonary arterial hypertension, do not take Viagra® or other PDE5 inhibitors, including tadalafil (Cialis®) or vardenafil (Levitra®). Viagra® also contains sildenafil. If you take too much sildenafil or take it together with these medicines, the chance for side effects will be higher.

Sildenafil should not be used with any other medicine or device that causes erections.

It is important to tell your doctor about any heart problems you have now or may have had in the past. This medicine can cause serious side effects in patients with heart problems.

If you experience a prolonged or painful erection for 4 hours or more, contact your doctor immediately. This condition may require prompt medical treatment to prevent serious and permanent damage to your penis.

If you experience a sudden loss of vision in one or both eyes, contact your doctor immediately.

Check with your doctor right away if you have a sudden decrease in hearing or loss of hearing, which may be accompanied by dizziness and ringing in the ears.

If you already use medicine for high blood pressure (hypertension), sildenafil could make your blood pressure go too low. Call your doctor right away if you have blurred vision, confusion, dizziness, faintness, or lightheadedness when getting up from a lying or sitting position suddenly, sweating, or unusual tiredness or weakness.

This medicine does not protect you against sexually transmitted diseases (including HIV or AIDS). Use protective measures and ask your doctor if you have any questions about this.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Common side effects of sildenafil

Some side effects of sildenafil may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Serious side effects of sildenafil

Along with its needed effects, sildenafil may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking sildenafil:

For healthcare professionals

Applies to sildenafil: intravenous solution, oral powder for reconstitution, oral tablet.

General adverse events

The most common adverse reactions occurring in patients with erectile dysfunction (ED) and pulmonary arterial hypertension (PAH) included headache, flushing, dyspepsia, abnormal vision, nasal congestion, back pain, myalgia, nausea, dizziness, rash, visual disturbance, cyanopsia, blurred vision, limb pain, priapism, upper respiratory infection, vomiting, bronchitis, pharyngitis, pyrexia, diarrhea, influenza, epistaxis.^[Ref]

Cardiovascular

• Very common (10% or more): Flushing (up to 19%)
• Rare (0.01% to 0.1%): Myocardial infarction, atrial fibrillation, unstable angina, tachycardia, palpitations
• Frequency not reported: Shock, angina pectoris, AV block, migraine, syncope, hypotension, postural hypotension, myocardial ischemia, cerebral thrombosis, cardiac arrest, heart failure, abnormal electrocardiogram, cardiomyopathy, vasodilation, abnormal electrocardiogram, increased heart rate
• Postmarketing reports: Myocardial infarction, sudden cardiac death, cardiac arrest, ventricular arrhythmia, hypertension, hypotensive events after the use with alpha-blockers, tachycardia, hypotension, syncope

Gastrointestinal

• Very common (10% or more): Dyspepsia (up to 17%), diarrhea
• Common (1% to 10%): Nausea, vomiting, dry mouth, gastritis, gastroesophageal reflux disease, hemorrhoids, abdominal distension
• Rare (less than 0.1%): Oral hypoesthesia
• Frequency not reported: Glossitis, colitis, dysphagia, gastroenteritis, esophagitis, stomatitis, gingivitis

Musculoskeletal

• Very common (10% or more): Pain in limb (up to 15%), myalgia (up to 14%), back pain (up to 13%)
• Frequency not reported: Arthritis, arthrosis, myalgia, tendon rupture, tenosynovitis, bone pain, myasthenia, synovitis
• Postmarketing reports: Pain in extremity, pain in jaw, arthralgia

Nervous system

• Very common (10% or more): Headache (up to 28% in ED; up to 49% in PAH)
• Common (1% to 10%): Dizziness, vertigo, paresthesia, tremor, burning sensation, migraine, hypoesthesia
• Uncommon (0.1% to 1%): Somnolence
• Rare (0.01% to 0.1%): Cerebrovascular accident, transient ischemic attack, syncope
• Frequency not reported: Ataxia, hypertonia, neuralgia, neuropathy, vertigo, depression, decreased reflexes/hyporeflexia, cerebral thrombosis, convulsion
• Postmarketing reports: Cerebrovascular hemorrhage, transient ischemic attack, subarachnoid hemorrhage, intracerebral hemorrhage, seizure, seizure recurrence, transient global amnesia

Ocular

• Very common (10% or more): Abnormal vision (up to 11%)
• Common (1% to 10%): Abnormal sensation in eye, chromatopsia, cyanopsia, diplopia, eye irritation, photophobia, retinal hemorrhage, visual acuity reduced, visual color distortion
• Uncommon (0.1% to 1%): Dry eye, lacrimal disorder, photopsia, ocular hyperemia, visual brightness, conjunctivitis, eye pain
• Rare (0.01% to 0.1%): Arteriosclerotic retinopathy, retinal disorder, glaucoma, visual field defect, myopia, asthenopia, vitreous floaters, iris disorder, mydriasis, halo vision, eye edema, eye swelling, eye disorder, conjunctival hyperemia, eyelid edema, scleral discoloration
• Frequency not reported: Eye hemorrhage, cataract, visual disturbance, xanthopsia, erythropsia
• Postmarketing reports: Diplopia, temporary vision loss/decreased vision, ocular redness or bloodshot appearance, ocular burning, ocular swelling/pressure, increased intraocular pressure, retinal edema, retinal vascular disease or bleeding, vitreous traction/detachment, non-arteritic anterior ischemic optic neuropathy (NAION)

Abnormal vision included a severity that was mild to moderate and transient, characterized predominantly by color tinge to vision, but also increased sensitivity to light, or blurred vision.

Lacrimation disorders included dry eye, lacrimal disorder, and lacrimation increased.

Visual color distortions included chloropsia, chromatopsia, cyanopsia, erythropsia, and xanthopsia.

Respiratory

• Very common (10% or more): Upper respiratory tract infection (up to 31%), bronchitis (up to 20%), pharyngitis (up to 18%)
• Common (1% to 10%): Nasal congestion, cough, epistaxis, dyspnea, sinusitis, rhinitis, bronchitis, pneumonia, rhinorrhea
• Uncommon (0.1% to 1%): Sinus congestion
• Frequency not reported: Asthma, laryngitis, increased sputum, increased cough, respiratory tract infection, throat tightness, nasal dryness, nasal edema, bronchopneumonia, hypoxia, stridor, pulmonary hypertension
• Postmarketing reports: Epistaxis, pulmonary hemorrhage

Dermatologic

• Common (1% to 10%): Rash, erythema, alopecia
• Frequency not reported: Face edema, photosensitivity reaction, urticaria, pruritus, sweating, skin ulcer, contact dermatitis, exfoliative dermatitis
• Postmarketing reports: Stevens-Johnson syndrome (SJS), Toxic epidermal necrolysis (TEN)

Hematologic

• Common (1% to 10%): Anemia
• Frequency not reported: Leukopenia
• Postmarketing reports: Vaso-occlusive crisis (in patients with PAH secondary to sickle cell disease)

Metabolic

• Common (1% to 10%): Increased weight, fluid retention
• Frequency not reported: Edema, gout, unstable diabetes, hyperglycemia, peripheral edema, hyperuricemia, hypoglycemic reaction, hypernatremia

Other

• Very common (10% or more): Pyrexia (up to 17%), influenza (up to 12%)
• Common (1% to 10%): Cellulitis, gynecomastia, breast enlargement, night sweats
• Uncommon (0.1% to 1%): Tinnitus, chest pain, feeling hot, fatigue
• Rare (0.01% to 0.1%): Deafness, irritability
• Frequency not reported: Asthenia, pain, chills, accidental fall, accidental injury, thirst, sudden decrease or loss of hearing, ear pain, flu syndrome, infection, herpes simplex
• Postmarketing reports: Sudden decrease or loss of hearing

Psychiatric

• Common (1% to 10%): Insomnia, anxiety
• Frequency not reported: Depression, abnormal dreams
• Postmarketing reports: Anxiety

Genitourinary

• Common (1% to 10%): Increased erection, urinary tract infection
• Uncommon (0.1% to 1%): Penile hemorrhage, hematospermia
• Frequency not reported: Cystitis, nocturia, urinary frequency, urinary incontinence, abnormal ejaculation, genital edema, anorgasmia, prostatic disorder
• Postmarketing reports: Prolonged erection, priapism

Renal

• Uncommon (0.1% to 1%): Hematuria

Hypersensitivity

• Uncommon (0.1% to 1%): Hypersensitivity
• Frequency not reported: Allergic reaction
• Postmarketing reports: Hypersensitivity reaction

Hepatic

• Frequency not reported: Abnormal liver tests

See also:

Frequently asked questions

• Cialis vs Viagra - What's the difference between them?
• Do you know these 11 amazing facts about Viagra?
• Is generic Viagra available in the U.S.?

Further information

Sildenafil side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer