Sildenafil Tablets: Formulation, Strengths & Product Context

What Are Sildenafil Tablets?

A sildenafil tablet is a finished solid oral dosage form in which sildenafil citrate, inactive formulation ingredients and a film coating are manufactured into a discrete pharmaceutical unit.

Current U.S. sildenafil tablets include ED-oriented products associated with the VIAGRA reference product and PAH-oriented products associated with the REVATIO tablet reference context.

Both contain the same active moiety, sildenafil, but product identity matters because strength sets, indication labeling, appearance and formulation details can differ.

Active Ingredient in Sildenafil Tablets

The pharmacologically active moiety is sildenafil. Current tablet descriptions commonly identify sildenafil citrate as the drug substance while stating strength as the amount of sildenafil to which that citrate salt is equivalent.

For example, a tablet labeled 50 mg contains sufficient sildenafil citrate to provide the equivalent of 50 mg sildenafil. The citrate portion means the physical mass of the salt is greater than the labeled sildenafil number.

This distinction is pharmaceutical terminology rather than evidence of a different active drug. Salt-versus-active-moiety chemistry is treated in depth on the sildenafil citrate page.

How Sildenafil Tablets Are Formulated

A sildenafil tablet combines the citrate drug substance with excipients that perform pharmaceutical functions such as bulking, binding, disintegration, lubrication and film coating.

Common formulation components across current sildenafil tablets include microcrystalline cellulose, calcium-phosphate excipients, croscarmellose sodium or other disintegrants, magnesium stearate, hypromellose and coating materials. Exact combinations vary by product.

Colorants and other coating ingredients can also differ. VIAGRA uses FD&C Blue No. 2 aluminum lake in its blue film coating, while some current generic tablets are white and contain no equivalent blue colorant and others use different coloring systems.

These formulation differences do not create a different sildenafil mechanism, but they show why inactive-ingredient information must be product-specific.

Sildenafil Is the Drug; Tablet Is the Form

Sildenafil identifies the active drug; tablet identifies one physical dosage form containing that drug.

The distinction matters because sildenafil is also available in oral suspension, oral film and intravenous formulations. Those products can have different strengths, concentrations, excipients, routes and handling requirements.

A tablet-specific statement therefore should not automatically be applied to every sildenafil formulation. The full dosage-form map is covered on the sildenafil formulations page.

Sildenafil Tablet Strengths

Current U.S. sildenafil tablet strengths depend on product context. VIAGRA and ED-oriented generic sildenafil tablets are commonly labeled 25 mg, 50 mg and 100 mg, while REVATIO and PAH-oriented generic sildenafil tablets use 20 mg.

Each number describes the sildenafil equivalent represented by one tablet. It does not by itself identify the indication or establish a dosing regimen.

The detailed cross-formulation strength map, including oral film, suspension and injection, remains on the sildenafil strengths page.

Common Sildenafil Tablet Strength Categories

The most commonly encountered U.S. sildenafil tablet strengths are 20 mg, 25 mg, 50 mg and 100 mg, but they do not represent one continuous interchangeable tablet family.

Twenty milligrams belongs to the REVATIO / PAH tablet context, while 25 mg, 50 mg and 100 mg belong to the VIAGRA / ED tablet context.

FDA's current product-specific generic guidance reinforces that distinction by treating the 20 mg tablet and the 25/50/100 mg tablets as products associated with separate reference products for generic-development purposes.

This is a regulatory product distinction, not evidence that the underlying sildenafil molecule differs.

Viagra Tablet Context

Current U.S. VIAGRA is formulated as blue, film-coated, rounded-diamond-shaped sildenafil-citrate tablets equivalent to 25 mg, 50 mg or 100 mg sildenafil.

Its inactive ingredients include microcrystalline cellulose, anhydrous dibasic calcium phosphate, croscarmellose sodium, magnesium stearate, hypromellose, titanium dioxide, lactose, triacetin and FD&C Blue No. 2 aluminum lake.

These appearance and excipient details describe VIAGRA specifically. A generic sildenafil tablet can meet regulatory requirements while looking different and using a different inactive-ingredient composition.

The brand relationship itself is covered on the sildenafil and Viagra page.

Revatio Tablet Context

Current REVATIO tablets are white to off-white, film-coated, round tablets containing sildenafil citrate equivalent to 20 mg sildenafil.

Current labeling lists anhydrous dibasic calcium phosphate, croscarmellose sodium, hypromellose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, titanium dioxide and triacetin as tablet inactive ingredients.

The 20 mg tablet belongs to the WHO Group I pulmonary arterial hypertension product framework rather than the VIAGRA ED tablet framework.

The full brand and formulation relationship is covered on the sildenafil and Revatio page.

Generic Sildenafil Tablets

Generic sildenafil tablets contain the same active moiety as their reference sildenafil products, but generic does not mean visually or compositionally identical.

Current ED-oriented generics are available in 25 mg, 50 mg and 100 mg strengths. Current labels show examples ranging from green oval film-coated tablets to white round or diamond-shaped tablets, depending on manufacturer.

Inactive ingredients also differ. One current generic formulation contains polyvinyl alcohol, talc and polyethylene glycol in its coating system, while another uses a simpler hypromellose, titanium-dioxide and triacetin coating system.

Separate generic 20 mg sildenafil tablets correspond to the PAH-oriented reference-product context. The broader generic-product framework remains on the generic sildenafil page.

Ingredients in Sildenafil Tablets

All sildenafil tablets contain an active drug component plus inactive formulation ingredients. The exact inactive-ingredient list should be taken from the specific dispensed product rather than assumed from the word sildenafil.

VIAGRA and REVATIO illustrate both similarity and difference. Both use sildenafil citrate and share several common excipients such as microcrystalline cellulose, calcium phosphate, croscarmellose sodium and magnesium stearate, but their finished products differ in strength, appearance and parts of the coating system.

Generic manufacturers can use alternative approved excipient combinations while still producing a sildenafil tablet that meets regulatory requirements.

A complete product-by-product ingredient breakdown would duplicate the dedicated sildenafil ingredients page, so this section remains a formulation overview.

Sildenafil Tablets vs Oral Suspension

Tablet and suspension products contain sildenafil but package the active drug in fundamentally different physical forms.

REVATIO provides a useful same-product-family example: its tablet contains 20 mg sildenafil per tablet, while its powder becomes a 10 mg/mL suspension after reconstitution. LIQREV is a separate ready-to-use 10 mg/mL sildenafil suspension.

The concentration number in a liquid therefore cannot be compared directly with a tablet milligram number without specifying the volume involved. Formulation, preparation and storage also differ.

The dedicated sildenafil tablets vs oral suspension page handles the full route/form comparison.

Sildenafil Tablets vs Injection

Sildenafil tablets require oral administration and gastrointestinal absorption, while REVATIO injection delivers sildenafil directly by the intravenous route.

Current REVATIO injection contains 10 mg in 12.5 mL, or 0.8 mg/mL. That concentration expression is fundamentally different from the 20 mg-per-tablet representation of the REVATIO oral tablet.

Sharing sildenafil as the active moiety does not make oral tablets and injection milligram-for-milligram interchangeable. Route, bioavailability and the product-specific label determine how the formulations are interpreted.

The full route comparison belongs on the oral vs injectable sildenafil page.

Tablet Bioequivalence and Generic Products

Generic sildenafil tablet approval is not based only on matching the active ingredient name and nominal strength. FDA uses product-specific bioequivalence and dissolution requirements to establish comparability to the appropriate reference product.

Current FDA product-specific guidance recommends an in-vivo fasting bioequivalence study using the 100 mg strength, with sildenafil as the primary analyte and N-desmethyl sildenafil reported as supportive metabolite data. Lower strengths can qualify for waiver approaches when the specified proportional-formulation and dissolution conditions are satisfied.

An especially important sildenafil-specific point is that the 20 mg tablet and the 25 mg, 50 mg and 100 mg tablets correspond to two separate reference products. FDA therefore treats them as distinct generic-development contexts rather than as one universal tablet family.

The statistical 90% confidence-interval framework and interpretation of AUC and Cmax belong on the sildenafil bioequivalence page.

Why Sildenafil Tablet Labels Can Differ

Two tablets can both contain sildenafil while legitimately carrying different product labeling because FDA approval applies to specific finished products rather than to the active ingredient in isolation.

The clearest distinction is indication context: VIAGRA-type 25/50/100 mg tablets are labeled for erectile dysfunction, while REVATIO-type 20 mg tablets belong to the WHO Group I pulmonary arterial hypertension framework.

Manufacturer-specific generic labels can also differ in tablet description, inactive ingredients, packaging, storage wording and parts of the patient information while remaining tied to the appropriate reference product.

The exact dispensed product label is therefore the correct source for tablet appearance, ingredient and package-specific information.

Common Sildenafil Tablet Terminology

Several pharmaceutical terms are easily collapsed when sildenafil tablets are discussed. Separating them makes product labels easier to interpret.

Sildenafil identifies the active moiety; sildenafil citrate identifies the salt form used as drug substance; film-coated tablet identifies the dosage form; strength identifies the sildenafil amount represented by each tablet; and brand or generic name identifies the finished product context.

Reference listed drug and bioequivalence are separate regulatory concepts used when generic products are developed and evaluated.

Where to Find More Sildenafil Tablet Information

This page provides the tablet-level product overview: active moiety, strength families, formulation differences, representative excipients, brand contexts and generic-tablet regulation.

Dedicated pages go deeper into individual subjects so that this tablet hub does not duplicate the full strength, ingredient, formulation or bioequivalence references.