Sildenafil 20 mg Tablet, Film Coated, 10-count
🆔 Identity & classification
Where does this data come from?
🏷️ RxNorm drug class
This medicine belongs to the Phosphodiesterase 5 Inhibitor class.
Where does this data come from?
🏭 Manufacturer & labeler
Where does this data come from?
🩺 Clinical
Sildenafil (Viagra) is used to treat erectile dysfunction (impotence; inability to get or keep an erection) in men. Sildenafil (Liqrev, Revatio) is used to improve the ability to exercise in adults (Liqrev, Revatio) and children 1 year of age and older (Revatio) with pulmonary arterial hypertension (PAH; high blood pressure in the vessels carrying blood to the lungs, causing shortness of breath, dizziness, and tiredness). Sildenafil is in a class of medications called phosphodiesterase (PDE) inhibitors. Sildenafil treats erectile dysfunction by increasing blood flow to the penis during sexual...
Read the full MedlinePlus article ↗- For erectile dysfunction, you take sildenafil only when you need it — about 30 minutes to 1 hour before sexual activity works best, though anywhere from 30 minutes to 4 hours ahead...
- Can I take Viagra or generic sildenafil just before sex, or do I need to take it every day?
- Both sildenafil and nitrates lower blood pressure, and together their effect on blood pressure can be dangerously large — we're talking about a drop severe enough to cause fainting...
- Why can't I take sildenafil with nitroglycerin or other nitrate medicines?
Patient education
Supplement & herbal interactions
Some supplements/herbs that may interact with Sildenafil Citrate — tap one for details:
Where does this data come from?
Ask a licensed pharmacist directly — free, answered by our team.
🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
Where does this data come from?
IACT rows and label-wide narrative are kept separate; availability and product-level specificity depend on the submitted label.Inactive ingredient FAQ
Are inactive ingredients the same for every manufacturer?
Why might an inactive ingredient be missing?
Can inactive ingredients matter?
💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per each | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | Not in the retail survey — common for institutional, discontinued, or low-volume packs. | |
| Medicaid paysCMS SDUD · 12 mo | No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data. | |
| Medicare drug plans payPart D · Q2 2026 | $0.4421 | $4.42 / 10 tablets |
Where does this data come from?
🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Sildenafil 20 mg 00904-6671-04 | Major | 30 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 27241-0124-03 | Ajanta | 90 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 31722-0776-05 | Camber | 500 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 33342-0121-10 | Macleods | 90 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 33342-0536-10 | Macleods | 90 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 50268-0717-15 | AvPAK | 50 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 60687-0788-21 | American | 1 tablet | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 62135-0372-90 | Chartwell | 90 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 65162-0351-09 | Amneal | 90 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 65862-0688-90 | Aurobindo | 90 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 68001-0363-05 | BluePoint | 90 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 68001-0597-05 | BluePoint | 90 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil Citrate 20 mg 72888-0018-00 | Advagen | 1000 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 82009-0094-90 | Quallent | 90 tablets | $0.051 | AB | Availability likely | — |
| Sildenafil 20 mg 13668-0185-05 | Torrent | 500 tablets | $0.077 | AB | FDA listed | — |
| Sildenafil Citrate 20 mg 52817-0295-00 | TruPharma | 1000 tablets | $0.077 | AB | FDA listed | — |
| Sildenafil 20 mg 59762-0033-01 | Mylan | 90 tablets | $0.077 | AB | Discontinued | — |
| Revatio 20 mg 00069-4190-68 | PFIZER | 90 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 42291-0937-90 | AvKARE | 90 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 43063-0982-10 | PD-Rx | 10 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mgthis 43353-0345-10 | Aphena | 10 tablets | — | AB | Discontinued | — |
| Sildenafil Citrate 20 mg 50090-3905-00 | A-S | 30 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 50090-5236-00 | A-S | 30 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 51407-0987-90 | Golden | 90 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 51655-0172-20 | Northwind | 20 tablets | — | AB | FDA listed | — |
| Sildenafil Citrate 20 mg 51655-0793-20 | Northwind | 20 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 53746-0351-90 | Amneal | 90 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 55154-4307-00 | Cardinal | 10 tablets | — | AB | FDA listed | — |
| Revatio 20 mg 58151-0402-77 | Viatris | 90 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 59746-0471-05 | Jubilant | 500 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 63187-0619-10 | Proficient | 10 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 63187-0789-10 | Proficient | 10 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 63187-0813-10 | Proficient | 10 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 63629-5029-00 | Bryant | 50 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 68071-2072-01 | NuCare | 10 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 68071-2213-09 | NuCare | 90 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 68071-2537-09 | NuCare | 90 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 68071-2602-03 | NuCare | 30 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 68071-3954-09 | NuCare | 90 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 68071-4517-09 | NuCare | 90 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 68071-5115-06 | NuCare | 60 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 68788-7974-03 | Preferred | 30 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 70518-3433-00 | REMEDYREPACK | 30 tablets | — | AB | Discontinued | — |
| Sildenafil 20 mg 70518-4596-00 | REMEDYREPACK | 250 tablets | — | AB | FDA listed | — |
| Sildenafil Citrate 20 mg 71205-0305-10 | Proficient | 10 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 71205-0509-30 | Proficient | 30 tablets | — | — | FDA listed | — |
| Sildenafil Citrate 20 mg 71205-0623-30 | Proficient | 30 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 71335-1005-01 | Bryant | 10 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 71335-1638-01 | Bryant | 10 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 71335-1649-00 | Bryant | 50 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 71335-1963-00 | Bryant | 50 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 71335-2657-00 | Bryant | 50 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 72162-2363-09 | Bryant | 90 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 72189-0298-20 | DirectRx | 20 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 72865-0105-90 | XLCare | 90 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 76420-0061-30 | Asclemed | 30 tablets | — | AB | FDA listed | — |
| Sildenafil Citrate 20 mg 76420-0613-30 | Asclemed | 30 tablets | — | AB | FDA listed | — |
| Sildenafil Citrate 20 mg 80425-0304-01 | Advanced | 30 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 82804-0185-30 | Proficient | 30 tablets | — | AB | FDA listed | — |
| Sildenafil 20 mg 82804-0243-30 | Proficient | 30 tablets | — | AB | FDA listed | — |
| Sildenafil Citrate 20 mg 82868-0094-30 | Northwind | 30 tablets | — | AB | FDA listed | — |
Where does this data come from?
⏳ Availability & generic status
FDA-approved generic versions are listed, and recent pricing/market data suggests they may be available — see Therapeutic equivalents.
Why the date isn’t exact: Generic timing can change because patents may be challenged, settled, licensed, added, removed, or worked around with a narrower label — and FDA approval does not always mean a pharmacy can get the generic today.
🛈 What do these terms mean?
- Patent
- Legal protection listed in the Orange Book that may delay generic approval or launch. Issued by the U.S. Patent & Trademark Office.
- Substance patent
- Covers the active drug molecule itself — the hardest to design around. A generic generally can’t launch until it expires.
- Formulation (product) patent
- Covers a specific formulation or dosage form. A generic can sometimes work around it with a different formulation.
- Method-of-use patent
- A patent covering one specific approved use of the drug — not necessarily the whole molecule. A generic can sometimes launch with a “skinny label” that carves out the protected use and keeps the others.
- Skinny label
- A generic label that omits a still-patented use when the FDA allows it — letting a generic reach the market for the unprotected uses.
- Exclusivity
- FDA-granted marketing protection, separate from patents — e.g. 5-yr new chemical entity, 7-yr orphan drug, or a +6-month pediatric extension.
- Paragraph IV
- A generic applicant’s formal challenge to a listed patent. It can potentially lead to earlier generic entry, but often involves litigation or a settlement.
- RLD / RS
- Reference Listed Drug — the brand product the FDA uses as the reference for generic applications. Reference Standard — the product the FDA expects generics to compare against in bioequivalence testing.
- TE / AB rating
- FDA therapeutic-equivalence rating. An AB rating generally means the FDA considers a generic therapeutically equivalent to — and substitutable for — the brand.
- LOE (loss of exclusivity)
- The latest patent or exclusivity currently listed — the loss-of-exclusivity / latest-listed-protection date shown on this page. Paragraph-IV challenges and settlements can move the real date earlier; FDA approval and a manufacturer’s decision to market can move it later.
Built from the FDA Orange Book. The bars above are scaled to each protection’s expiry; the red LOE marker is the last one to lapse.
| Code | What it grants | Expires |
|---|---|---|
| M-287 | New indication / labeling change (3-year) | Jan 31, 2026 |
| ODE-469 | Orphan Drug Exclusivity (7-year) | Jan 31, 2030 |
Is there a generic version of SILDENAFIL 20 MG TABLET?
The FDA approved a generic — why can’t I get it at my pharmacy yet?
Why do different websites show different generic release dates?
What does “FDA listed” mean?
What does a patent or protection date mean here?
What does “current Orange Book estimate” mean?
Can a generic come out before the last patent expires?
Can a generic come out after the listed dates?
What is the difference between patents and exclusivity?
Why are there multiple patent dates?
Where does this data come from?
📊 Medicare Part D spend CMS · PART D · 2026 (Q1)
📦 Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Status |
|---|---|---|---|
| 43353-0345-10 You're viewing this | 10 TABLET, FILM COATED in 1 BOTTLE (43353-345-10) | 2017-07-03 | Discontinued by firm |
| 43353-0345-20 | 20 TABLET, FILM COATED in 1 BOTTLE (43353-345-20) | 2017-07-03 | Discontinued by firm |
| 43353-0345-53 | 60 TABLET, FILM COATED in 1 BOTTLE (43353-345-53) | 2017-07-03 | Discontinued by firm |
You're viewing the smallest of 3 pack sizes for this product.
Pack size FAQ
What quantity is in NDC 43353-0345-10?
What is the difference between NDC 43353-0345-10 and NDC 43353-0345-20?
What NDC number is used to bill for this package of Sildenafil 20 mg Tablet, Film Coated?
🧭 About this NDC listing & data coverage
What data is (and isn’t) available for this NDC — tap to expand
| NDC identity (package / product / labeler codes) | ✓ Available |
| Labeler | ✓ Available |
| Product & package description | ✓ Available |
| Marketing category & status | ✓ Available |
| Active ingredient / dosage form / route | ✓ Available |
| FDA label (SPL via DailyMed) | ✓ Available |
| Package photos | — Not published for this NDC No photo available yet for this listing. |
| Inactive ingredients (structured) | — Not published for this NDC The labeler did not submit a structured excipient list, or no SPL is available. |
| NADAC pharmacy acquisition price (CMS) | — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey. |
| Orange Book / therapeutic-equivalence data | ✓ Available |
| HCPCS J-code billing crosswalk | — Not published for this NDC Most self-administered / retail products have no J-code — that is normal. |
| Medicaid utilization (CMS SDUD) | — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold. |
Questions about this listing
Why is there no price listed?
What does the discontinued status mean for this NDC?
Is the NDC printed on the package the same as the 11-digit billing NDC?
What do the three segments of this NDC mean?
Does this product come in other package sizes?
Who lists this product with the FDA?
Do I need a prescription for this product?
Where does this data come from?
📄 Full prescribing information FDA SPL
🎯 Indications and Usage ▾
1 INDICATIONS AND USAGE Sildenafil is indicated for the treatment of pulmonary arterial hypertension (WHO Group I) in adults to improve exercise ability and delay clinical worsening. The delay in clinical worsening was demonstrated when sildenafil was added to background epoprostenol therapy [see Clinical Studies (14) ] . Studies establishing effectiveness were short-term (12 to 16 weeks), included predominately patients with New York Heart Association (NYHA) Functional Class II–III symptoms and idiopathic etiology (71%) or associated with connective tissue disease (CTD) (25%).
Sildenafil is a phosphodiesterase-5 (PDE-5) inhibitor indicated for the treatment of pulmonary arterial hypertension (PAH) (WHO Group I) in adults to improve exercise ability and delay clinical worsening. Studies establishing effectiveness were short-term (12 to 16 weeks), and included predominately patients with NYHA Functional Class II–III symptoms. Etiologies were idiopathic (71%) or associated with connective tissue disease (25%).
( 1 ) Limitation of Use : Adding sildenafil to bosentan therapy does not result in any beneficial effect on exercise capacity. ( 1 , 14 ) Limitation of Use: Adding sildenafil to bosentan therapy does not result in any beneficial effect on exercise capacity [see Clinical Studies (14) ] .
⏱️ Dosage and Administration ▾
2 DOSAGE AND ADMINISTRATION Tablets: 20 mg three times a day, 4–6 hours apart ( 2 ) Sildenafil Tablets The recommended dose of sildenafil is 20 mg three times a day. Administer sildenafil doses 4–6 hours apart. In the clinical trial no greater efficacy was achieved with the use of higher doses. Treatment with doses higher than 20 mg three times a day is not recommended.
💊 Dosage Forms and Strengths ▾
3 DOSAGE FORMS AND STRENGTHS Tablets: 20 mg ( 3 ) Sildenafil Tablets White, film-coated, round tablets engraved with SDF20 containing sildenafil citrate equivalent to 20 mg of sildenafil.
⛔ Contraindications ▾
4 CONTRAINDICATIONS Sildenafil is contraindicated in patients with: Concomitant use of organic nitrates in any form, either regularly or intermittently, because of the greater risk of hypotension [see Warnings and Precautions (5.2) ] . Concomitant use of riociguat, a guanylate cyclase stimulator. PDE5 inhibitors, including sildenafil, may potentiate the hypotensive effects of riociguat.
Known hypersensitivity to sildenafil or any component of the tablet. Hypersensitivity, including anaphylactic reaction, anaphylactic shock and anaphylactoid reaction, has been reported in association with the use of sildenafil. Use with organic nitrates or riociguat ( 4 ) History of hypersensitivity reaction to sildenafil or any component of the tablet ( 4 )
⚠️ Warnings and Cautions ▾
5 WARNINGS AND PRECAUTIONS Increased mortality with increasing doses in pediatric patients. Not recommended for use in pediatric patients. ( 5.1 ) Vasodilation effects may be more common in patients with hypotension or on antihypertensive therapy.
( 5.2 ) Use in pulmonary veno-occlusive disease may cause pulmonary edema and is not recommended. ( 5.3 ) Hearing or visual impairment: Seek medical attention if sudden decrease or loss of vision or hearing occurs. ( 5.5 , 5.6 ) Pulmonary hypertension secondary to sickle cell disease: sildenafil may cause serious vaso-occlusive crises.
( 5.9 )
5.1Mortality with Pediatric Use In a long-term trial in pediatric patients with PAH, an increase in mortality with increasing sildenafil dose was observed. Deaths were first observed after about 1 year and causes of death were typical of patients with PAH. Use of sildenafil, particularly chronic use, is not recommended in children [see Use in Specific Populations (8.4) ].
5.2Hypotension Sildenafil has vasodilatory properties, resulting in mild and transient decreases in blood pressure. Before prescribing sildenafil, carefully consider whether patients with certain underlying conditions could be adversely affected by such vasodilatory effects (e.g., patients on antihypertensive therapy or with resting hypotension [BP less than 90/50], fluid depletion, severe left ventricular outflow obstruction, or autonomic dysfunction). Monitor blood pressure when co-administering blood pressure lowering drugs with sildenafil.
5.3Worsening Pulmonary Vascular Occlusive Disease Pulmonary vasodilators may significantly worsen the cardiovascular status of patients with pulmonary veno-occlusive disease (PVOD). Since there are no clinical data on administration of sildenafil to patients with veno-occlusive disease, administration of sildenafil to such patients is not recommended. Should signs of pulmonary edema occur when sildenafil is administered, consider the possibility of associated PVOD.
5.4Epistaxis The incidence of epistaxis was 13% in patients taking sildenafil with PAH secondary to CTD. This effect was not seen in idiopathic PAH (sildenafil 3%, placebo 2%) patients. The incidence of epistaxis was also higher in sildenafil-treated patients with a concomitant oral vitamin K antagonist (9% versus 2% in those not treated with concomitant vitamin K antagonist).
The safety of sildenafil is unknown in patients with bleeding disorders or active peptic ulceration.
5.5Visual Loss When used to treat erectile dysfunction, non-arteritic anterior ischemic optic neuropathy (NAION), a cause of decreased vision including permanent loss of vision, has been reported postmarketing in temporal association with the use of phosphodiesterase type 5 (PDE-5) inhibitors, including sildenafil. Most, but not all, of these patients had underlying anatomic or vascular risk factors for developing NAION, including but not necessarily limited to: low cup to disc ratio ("crowded disc"), age over 50, diabetes, hypertension, coronary artery disease, hyperlipidemia and smoking.
Based on published literature, the annual incidence of NAION is 2.5-11.8 cases per 100,000 males aged ≥ 50 per year in the general population. An observational study evaluated whether recent, episodic use of PDE5 inhibitors (as a class), typical of erectile dysfunction treatment, was associated with acute onset of NAION. The results suggest an approximately 2-fold increase in the risk of NAION within 5 half-lives of PDE5 inhibitor use.
It is not possible to determine whether these events are related directly to the use of PDE-5 inhibitors, to the patient's underlying vascular risk factors or anatomical defects, to a combination of these factors, or to other factors. Advise patients to seek immediate medical attention in the event of a sudden loss of vision in one or both eyes while taking PDE-5 inhibitors, including sildenafil. Physicians should also discuss the increased risk of NAION with patients who have alread…
🤒 Adverse Reactions ▾
6 ADVERSE REACTIONS The following serious adverse events are discussed elsewhere in the labeling: Mortality with pediatric use [see Warnings and Precautions (5.1) and Use in Specific Populations (8.4) ] Hypotension [see Warnings and Precautions (5.2) ] Vision loss [see Warnings and Precautions (5.5) ] Hearing loss [see Warnings and Precautions (5.6) ] Priapism [see Warnings and Precautions (5.8) ] Vaso-occlusive crisis [see Warnings and Precautions (5.9) ] Most common adverse reactions greater than or equal to 3% and more frequent than placebo were epistaxis, headache, dyspepsia, flushing, insomnia, erythema, dyspnea, and rhinitis.
( 6.1 , 6.2 ) To report SUSPECTED ADVERSE REACTIONS, contact Greenstone LLC Professional Information Services at 1-800-438-1985 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
6.1Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Safety data of sildenafil in adults were obtained from the 12-week, placebo-controlled clinical study (Study 1) and an open-label extension study in 277 sildenafil-treated patients with PAH, WHO Group I [see Clinical Studies (14) ] .
The overall frequency of discontinuation in sildenafil-treated patients on 20 mg three times a day was 3% and was the same for the placebo group. In Study 1, the adverse reactions that were reported by at least 3% of sildenafil-treated patients (20 mg three times a day) and were more frequent in sildenafil-treated patients than in placebo-treated patients, are shown in Table 1. Adverse reactions were generally transient and mild to moderate in nature.
Table 1. Most Common Adverse Reactions in Patients with PAH in Study 1 (More Frequent in Sildenafil-Treated Patients than Placebo-Treated Patients and Incidence ≥3% in Sildenafil-Treated Patients) Placebo, % (n = 70) Sildenafil 20 mg three times a day, % (n = 69) Placebo-Subtracted, % Epistaxis 1 9 8 Headache 39 46 7 Dyspepsia 7 13 6 Flushing 4 10 6 Insomnia 1 7 6 Erythema 1 6 5 Dyspnea exacerbated 3 7 4 Rhinitis 0 4 4 Diarrhea 6 9 3 Myalgia 4 7 3 Pyrexia 3 6 3 Gastritis 0 3 3 Sinusitis 0 3 3 Paresthesia 0 3 3 At doses higher than the recommended 20 mg three times a day, there was a greater incidence of some adverse reactions including flushing, diarrhea, myalgia and visual disturbances.
Visual disturbances were identified as mild and transient, and were predominately color-tinge to vision, but also increased sensitivity to light or blurred vision. The incidence of retinal hemorrhage at the recommended sildenafil 20 mg three times a day was 1.4% versus 0% placebo and for all sildenafil doses studied was 1.9% versus 0% placebo. The incidence of eye hemorrhage at both 20 mg three times a day and at all doses studied was 1.4% for sildenafil versus 1.4% for placebo.
The patients experiencing these reactions had risk factors for hemorrhage including concurrent anticoagulant therapy. In a placebo-controlled fixed dose titration study (Study 2) of sildenafil (starting with recommended dose of 20 mg and increased to 40 mg and then 80 mg all three times a day) as an adjunct to intravenous epoprostenol in patients with PAH, the adverse reactions that were more frequent in the sildenafil + epoprostenol group than in the epoprostenol group (greater than 6% difference) are shown in Table 2 [see Clinical Studies (14) ] .
Table 2. Adverse Reactions (%) in patients with PAH in Study 2 (incidence in Sildenafil + Epoprostenol group at least 6% greater than Epoprostenol group) Sildenafil + Epoprostenol (n = 134) Epoprostenol (n = 131) (Sildenafil + Epoprostenol) minus Epoprostenol % Headache 57 34 23 Edema includes peripheral edema 25 13 14 Dyspepsia 16 2 14 Pain in extremity 17 6 11 Diarrhea 25 18 7 Nausea 25 18 7 Nasal congestion 9 2 7
6.2 Postmarketing Experience The followi…
🔄 Drug Interactions ▾
7 DRUG INTERACTIONS Concomitant alpha-blockers or amlodipine: Note additive blood pressure lowering effects. ( 7 ) Use with ritonavir and other potent CYP3A inhibitors: Not recommended. ( 7 , 12.3 ) Concomitant PDE-5 inhibitors: Avoid use with Viagra or other PDE-5 inhibitors.
( 5.7 ) Nitrates Concomitant use of sildenafil with nitrates in any form is contraindicated [see Contraindications (4) ] . Ritonavir and other Potent CYP3A Inhibitors Concomitant use of sildenafil with ritonavir and other potent CYP3A inhibitors is not recommended [see Clinical Pharmacology (12.3) ] . Other drugs that reduce blood pressure Alpha blockers .
In drug-drug interaction studies, sildenafil (25 mg, 50 mg, or 100 mg) and the alpha-blocker doxazosin (4 mg or 8 mg) were administered simultaneously to patients with benign prostatic hyperplasia (BPH) stabilized on doxazosin therapy. In these study populations, mean additional reductions of supine systolic and diastolic blood pressure of 7/7 mmHg, 9/5 mmHg, and 8/4 mmHg, respectively, were observed. Mean additional reductions of standing blood pressure of 6/6 mmHg, 11/4 mmHg, and 4/5 mmHg, respectively, were also observed.
There were infrequent reports of patients who experienced symptomatic postural hypotension. These reports included dizziness and light-headedness, but not syncope. Amlodipine .
When sildenafil 100 mg oral was co-administered with amlodipine, 5 mg or 10 mg oral, to hypertensive patients, the mean additional reduction on supine blood pressure was 8 mmHg systolic and 7 mmHg diastolic. Monitor blood pressure when co-administering blood pressure lowering drugs with sildenafil [see Warnings and Precautions (5.2) ] .
👥 Use in Specific Populations ▾
8 USE IN SPECIFIC POPULATIONS
8.1Pregnancy Pregnancy Category B There are no adequate and well-controlled studies of sildenafil in pregnant women. No evidence of teratogenicity, embryotoxicity, or fetotoxicity was observed in pregnant rats or rabbits dosed with sildenafil 200 mg/kg/day during organogenesis, a level that is, on a mg/m 2 basis, 32- and 68-times, respectively, the recommended human dose (RHD) of 20 mg three times a day. In a rat pre- and postnatal development study, the no-observed-adverse-effect dose was 30 mg/kg/day (equivalent to 5-times the RHD on a mg/m 2 basis).
8.2Labor and Delivery The safety and efficacy of sildenafil during labor and delivery have not been studied.
8.3Nursing Mothers It is not known if sildenafil or its metabolites are excreted in human breast milk. Because many drugs are excreted in human milk, caution should be exercised when sildenafil is administered to a nursing woman.
8.4Pediatric Use In a randomized, double-blind, multi-center, placebo-controlled, parallel-group, dose-ranging study, 234 patients with PAH, aged 1 to 17 years, body weight greater than or equal to 8 kg, were randomized, on the basis of body weight, to three dose levels of sildenafil, or placebo, for 16 weeks of treatment. Most patients had mild to moderate symptoms at baseline: WHO Functional Class I (32%), II (51%), III (15%), or IV (0.4%). One-third of patients had primary PAH; two-thirds had secondary PAH (systemic-to-pulmonary shunt in 37%; surgical repair in 30%).
Sixty-two percent of patients were female. Drug or placebo was administered three times a day. The primary objective of the study was to assess the effect of sildenafil on exercise capacity as measured by cardiopulmonary exercise testing in pediatric patients developmentally able to perform the test (n = 115).
Administration of sildenafil did not result in a statistically significant improvement in exercise capacity in those patients. No patients died during the 16-week controlled study. After completing the 16-week controlled study, a patient originally randomized to sildenafil remained on his/her dose of sildenafil or, if originally randomized to placebo, was randomized to low-, medium-, or high-dose sildenafil.
After all patients completed 16 weeks of follow-up in the controlled study, the blind was broken and doses were adjusted as clinically indicated. Patients treated with sildenafil were followed for a median of 4.6 years (range 2 days to 8.6 years). Mortality during the long-term study, by originally assigned dose, is shown in Figure 1: Figure 1: Kaplan-Meier Plot of Mortality by Sildenafil Dose During the study, there were 42 reported deaths, with 37 of these deaths reported prior to a decision to titrate subjects to a lower dosage because of a finding of increased mortality with increasing sildenafil doses.
For the survival analysis which included 37 deaths, the hazard ratio for high dose compared to low dose was 3.9, p=0.007. Causes of death were typical of patients with PAH. Use of sildenafil, particularly chronic use, is not recommended in children.
Figure 1
8.5Geriatric Use Clinical studies of sildenafil did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy [see Clinical Pharmacology (12.3) ] .
8.6Patients with Hepatic Impairment No dose adjustment for mild to moderate impairment is required. Severe impairment has not been studied [see Clinical Pharmacology (12.3) ] .
8.7Patients with Renal Impairment No dose adjustment is required (including severe impairment CLcr < 30 mL/min) [see Clinical Pharmacology (12.3) ] .
🤰 Pregnancy ▾
8.1Pregnancy Pregnancy Category B There are no adequate and well-controlled studies of sildenafil in pregnant women. No evidence of teratogenicity, embryotoxicity, or fetotoxicity was observed in pregnant rats or rabbits dosed with sildenafil 200 mg/kg/day during organogenesis, a level that is, on a mg/m 2 basis, 32- and 68-times, respectively, the recommended human dose (RHD) of 20 mg three times a day. In a rat pre- and postnatal development study, the no-observed-adverse-effect dose was 30 mg/kg/day (equivalent to 5-times the RHD on a mg/m 2 basis).
🧒 Pediatric Use ▾
8.4Pediatric Use In a randomized, double-blind, multi-center, placebo-controlled, parallel-group, dose-ranging study, 234 patients with PAH, aged 1 to 17 years, body weight greater than or equal to 8 kg, were randomized, on the basis of body weight, to three dose levels of sildenafil, or placebo, for 16 weeks of treatment. Most patients had mild to moderate symptoms at baseline: WHO Functional Class I (32%), II (51%), III (15%), or IV (0.4%). One-third of patients had primary PAH; two-thirds had secondary PAH (systemic-to-pulmonary shunt in 37%; surgical repair in 30%).
Sixty-two percent of patients were female. Drug or placebo was administered three times a day. The primary objective of the study was to assess the effect of sildenafil on exercise capacity as measured by cardiopulmonary exercise testing in pediatric patients developmentally able to perform the test (n = 115).
Administration of sildenafil did not result in a statistically significant improvement in exercise capacity in those patients. No patients died during the 16-week controlled study. After completing the 16-week controlled study, a patient originally randomized to sildenafil remained on his/her dose of sildenafil or, if originally randomized to placebo, was randomized to low-, medium-, or high-dose sildenafil.
After all patients completed 16 weeks of follow-up in the controlled study, the blind was broken and doses were adjusted as clinically indicated. Patients treated with sildenafil were followed for a median of 4.6 years (range 2 days to 8.6 years). Mortality during the long-term study, by originally assigned dose, is shown in Figure 1: Figure 1: Kaplan-Meier Plot of Mortality by Sildenafil Dose During the study, there were 42 reported deaths, with 37 of these deaths reported prior to a decision to titrate subjects to a lower dosage because of a finding of increased mortality with increasing sildenafil doses.
For the survival analysis which included 37 deaths, the hazard ratio for high dose compared to low dose was 3.9, p=0.007. Causes of death were typical of patients with PAH. Use of sildenafil, particularly chronic use, is not recommended in children.
Figure 1
🧓 Geriatric Use ▾
8.5Geriatric Use Clinical studies of sildenafil did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy [see Clinical Pharmacology (12.3) ] .
🆘 Overdosage ▾
10 OVERDOSAGE In studies with healthy volunteers of single doses up to 800 mg, adverse events were similar to those seen at lower doses but rates and severities were increased. In cases of overdose, standard supportive measures should be adopted as required. Renal dialysis is not expected to accelerate clearance as sildenafil is highly bound to plasma proteins and it is not eliminated in the urine.
🧬 Clinical Pharmacology ▾
12 CLINICAL PHARMACOLOGY
12.1Mechanism of Action Sildenafil is an inhibitor of cGMP specific phosphodiesterase type-5 (PDE-5) in the smooth muscle of the pulmonary vasculature, where PDE-5 is responsible for degradation of cGMP. Sildenafil, therefore, increases cGMP within pulmonary vascular smooth muscle cells resulting in relaxation. In patients with PAH, this can lead to vasodilation of the pulmonary vascular bed and, to a lesser degree, vasodilatation in the systemic circulation.
Studies in vitro have shown that sildenafil is selective for PDE-5. Its effect is more potent on PDE-5 than on other known phosphodiesterases (10-fold for PDE-6, greater than 80-fold for PDE-1, greater than 700-fold for PDE-2, PDE-3, PDE-4, PDE-7, PDE-8, PDE-9, PDE-10, and PDE-11). The approximately 4,000-fold selectivity for PDE-5 versus PDE-3 is important because PDE-3 is involved in control of cardiac contractility.
Sildenafil is only about 10-fold as potent for PDE-5 compared to PDE-6, an enzyme found in the retina and involved in the phototransduction pathway of the retina. This lower selectivity is thought to be the basis for abnormalities related to color vision observed with higher doses or plasma levels [see Clinical Pharmacology (12.2) ] . In addition to pulmonary vascular smooth muscle and the corpus cavernosum, PDE-5 is also found in other tissues including vascular and visceral smooth muscle and in platelets.
The inhibition of PDE-5 in these tissues by sildenafil may be the basis for the enhanced platelet anti-aggregatory activity of nitric oxide observed in vitro, and the mild peripheral arterial-venous dilatation in vivo.
12.2Pharmacodynamics Effects of Sildenafil on Hemodynamic Measures Patients on all sildenafil doses achieved a statistically significant reduction in mean pulmonary arterial pressure (mPAP) compared to those on placebo in a study with no background vasodilators [ Study 1 in Clinical Studies (14) ] . Data on other hemodynamic measures for the sildenafil 20 mg three times a day and placebo dosing regimens is displayed in Table 3. The relationship between these effects and improvements in 6-minute walk distance is unknown.
Table 3. Changes from Baseline in Hemodynamic Parameters at Week 12 [mean (95% CI)] for the Sildenafil 20 mg Three Times a Day and Placebo Group Placebo (n = 65) The number of patients per treatment group varied slightly for each parameter due to missing assessments. Sildenafil 20 mg three times a day (n = 65) mPAP = mean pulmonary arterial pressure; PVR= pulmonary vascular resistance; SVR = systemic vascular resistance; RAP = right atrial pressure; CO = cardiac output; HR = heart rate mPAP (mmHg) 0.6 (-0.8, 2.0) -2.1 (-4.3, 0.0) PVR (dyn∙s/cm 5 ) 49 (-54, 153) -122 (-217, -27) SVR (dyn∙s/cm 5 ) -78 (-197, 41) -167 (-307, -26) RAP (mmHg) 0.3 (-0.9, 1.5) -0.8 (-1.9, 0.3) CO (L/min) -0.1 (-0.4, 0.2) 0.4 (0.1, 0.7) HR (beats/min) -1.3 (-4.1, 1.4) -3.7 (-5.9, -1.4) In another study evaluating lower doses of sildenafil 1 mg, 5 mg and 20 mg [Study 3 in Clinical Studies (14)] , there were no significant differences in the effects on hemodynamic variables between doses.
Effects of Sildenafil on Blood Pressure Single oral doses of sildenafil 100 mg administered to healthy volunteers produced decreases in supine blood pressure (mean maximum decrease in systolic/diastolic blood pressure of 8/5 mmHg). The decrease in blood pressure was most notable approximately 1–2 hours after dosing, and was not different from placebo at 8 hours. Similar effects on blood pressure were noted with 25 mg, 50 mg and 100 mg doses of sildenafil, therefore the effects are not related to dose or plasma levels within this dosage range.
Larger effects were recorded among patients receiving concomitant nitrates [see Contraindications (4) ] . Single oral doses of sildenafil up to 100 mg in healthy volunteers produced no clinically relevant effects on ECG. After chronic dosing of 80 mg three times a day to patients with PAH, no clinical…
🧬 Mechanism of Action ▾
12.1Mechanism of Action Sildenafil is an inhibitor of cGMP specific phosphodiesterase type-5 (PDE-5) in the smooth muscle of the pulmonary vasculature, where PDE-5 is responsible for degradation of cGMP. Sildenafil, therefore, increases cGMP within pulmonary vascular smooth muscle cells resulting in relaxation. In patients with PAH, this can lead to vasodilation of the pulmonary vascular bed and, to a lesser degree, vasodilatation in the systemic circulation.
Studies in vitro have shown that sildenafil is selective for PDE-5. Its effect is more potent on PDE-5 than on other known phosphodiesterases (10-fold for PDE-6, greater than 80-fold for PDE-1, greater than 700-fold for PDE-2, PDE-3, PDE-4, PDE-7, PDE-8, PDE-9, PDE-10, and PDE-11). The approximately 4,000-fold selectivity for PDE-5 versus PDE-3 is important because PDE-3 is involved in control of cardiac contractility.
Sildenafil is only about 10-fold as potent for PDE-5 compared to PDE-6, an enzyme found in the retina and involved in the phototransduction pathway of the retina. This lower selectivity is thought to be the basis for abnormalities related to color vision observed with higher doses or plasma levels [see Clinical Pharmacology (12.2) ] . In addition to pulmonary vascular smooth muscle and the corpus cavernosum, PDE-5 is also found in other tissues including vascular and visceral smooth muscle and in platelets.
The inhibition of PDE-5 in these tissues by sildenafil may be the basis for the enhanced platelet anti-aggregatory activity of nitric oxide observed in vitro, and the mild peripheral arterial-venous dilatation in vivo.
📦 How Supplied / Storage and Handling ▾
16 HOW SUPPLIED/STORAGE AND HANDLING Sildenafil tablets are supplied as white, film-coated, round tablets containing sildenafil citrate equivalent to the nominally indicated amount of sildenafil as follows: Sildenafil Tablets Package Configuration Strength NDC Engraving on Tablet Bottle of 90 Tablets 20 mg 59762-0033-1 SDF20 Recommended Storage for Sildenafil Tablets: Store at controlled room temperature 20°C – 25°C (68°F – 77°F) ; excursions permitted to 15°C – 30°C (59°F –86°F) [see USP Controlled Room Temperature].
📦 Storage and Handling ▾
Recommended Storage for Sildenafil Tablets: Store at controlled room temperature 20°C – 25°C (68°F – 77°F) ; excursions permitted to 15°C – 30°C (59°F –86°F) [see USP Controlled Room Temperature].
📋 Description ▾
11 DESCRIPTION Sildenafil, phosphodiesterase-5 (PDE-5) inhibitor, is the citrate salt of sildenafil, a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type-5 (PDE-5). Sildenafil is also marketed as VIAGRA ® for erectile dysfunction. Sildenafil citrate is designated chemically as 1-[[3-(6,7-dihydro-1-methyl-7-oxo-3-propyl-1 H -pyrazolo [4,3- d ] pyrimidin-5-yl)-4-ethoxyphenyl] sulfonyl]-4-methylpiperazine citrate and has the following structural formula: Sildenafil citrate is a white to off-white crystalline powder with a solubility of 3.5 mg/mL in water and a molecular weight of 666.7.
Sildenafil Tablets: Sildenafil is formulated as white, film-coated round tablets for oral administration. Each tablet contains sildenafil citrate equivalent to 20 mg of sildenafil. In addition to the active ingredient, sildenafil citrate, each tablet contains the following inactive ingredients: microcrystalline cellulose, anhydrous dibasic calcium phosphate, croscarmellose sodium, magnesium stearate, hypromellose, titanium dioxide, lactose monohydrate, and triacetin.
Chemical Structure
💬 Information for Patients ▾
17 PATIENT COUNSELING INFORMATION See FDA-approved patient labeling ( Patient Information ) Inform patients of contraindication of sildenafil with regular and/or intermittent use of organic nitrates. Inform patients that sildenafil is also marketed as VIAGRA for erectile dysfunction. Advise patients taking sildenafil not to take VIAGRA or other PDE-5 inhibitors.
Advise patients to seek immediate medical attention in the event of a sudden loss of vision in one or both eyes while taking sildenafil. Such an event may be a sign of NAION. Advise patients to seek prompt medical attention in the event of sudden decrease or loss of hearing while taking sildenafil.
These events may be accompanied by tinnitus and dizziness.