Viagra (Sildenafil)

Name: Viagra
Brand: Viatris
SKU: 2174
Availability: InStock

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Product

Manufacturer

Country

Dosage

Qty-Price (USD)

Type:

Product: Viagra

Manufacturer: Viatris

Country: Canada

Dosage: 50 mg

Qty-Price (USD):

Type:

Product: Viagra

Manufacturer: Viatris

Country: Turkey

Dosage: 50 mg

Qty-Price (USD):

Type:

Product: Viagra

Manufacturer: Pfizer

Country: Turkey

Dosage: 100 mg

Qty-Price (USD):

Type:

Product: Viagra

Manufacturer: Aspen

Country: New Zealand

Dosage: 100 mg

Qty-Price (USD):

Type:

Product: Viagra

Manufacturer: Viatris

Country: Canada

Dosage: 100 mg

Qty-Price (USD):

Generic Equivalent of Viagra

Type

Product

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Country

Dosage

Qty-Price (USD)

Type:

Product: Sildenafil

Manufacturer: Generic

Country: Canada

Dosage: 25 mg

Qty-Price (USD):

Type:

Product: Sildenafil

Manufacturer: Generic

Country: United Kingdom

Dosage: 25 mg

Qty-Price (USD):

Type:

Product: Sildenafil

Manufacturer: Generic

Country: Canada

Dosage: 50 mg

Qty-Price (USD):

Type:

Product: Sildenafil

Manufacturer: Generic

Country: United Kingdom

Dosage: 50 mg

Qty-Price (USD):

Type:

Product: Sildenafil (Suhagra - Cipla)

Manufacturer: Generic

Country: India

Dosage: 50 mg

Qty-Price (USD):

Type:

Product: Sildenafil

Manufacturer: Generic

Country: Canada

Dosage: 100 mg

Qty-Price (USD):

Type:

Product: Sildenafil

Manufacturer: Generic

Country: United Kingdom

Dosage: 100 mg

Qty-Price (USD):

Type:

Product: Sildenafil (Silagra - Cipla)

Manufacturer: Generic

Country: India

Dosage: 100 mg

Qty-Price (USD):

Type:

Product: Sildenafil (Suhagra - Cipla)

Manufacturer: Generic

Country: India

Dosage: 100 mg

Qty-Price (USD):

Viagra Information

medically reviewed by Carol Hou (BSc. Pharm) on October 16, 2025.

A licensed pharmacist (Licensed Community Pharmacies Directory | College of Pharmacists of British Columbia) with over 20 years of experience in medication management, specifically medication safety, she has reviewed the information for accuracy and completeness.

Viagra and Sildenafil at CanadaPharmacyOnline.com

The brand-name drug Viagra (sildenafil citrate) was initially developed by Pfizer. The brand is currently primarily commercialized globally by Viatris and Aspen Pharma. It is available in numerous countries worldwide, including Canada, New Zealand, and Turkey.

Sildenafil is also known by another brand name, Revatio, which is specifically used to treat pulmonary arterial hypertension (PAH).

Generic sildenafil is sourced from manufacturers that meet applicable regulatory standards. The specific manufacturer of your dispensed medication may vary.

Important Information about Generic Sildenafil:

Generic sildenafil contains the same active ingredient as the brand-name Viagra and is required to meet the same safety, effectiveness, and quality standards as the brand-name product. This means it is designed to work in the same way as Viagra. Studies have shown that generic sildenafil is bioequivalent to brand-name Viagra, meaning it has a similar absorption rate and reaches similar concentrations in the bloodstream. However, individual responses to medication can vary due to factors such as metabolism, genetics, and other health conditions.

For more information about generic drug approval and bioequivalence, please visit Access to Generic Drugs in Canada | Canada.ca.

Dosage:

The brand Viagra and its generic equivalent, sildenafil, are commonly available in the strengths of 25 mg, 50 mg, and 100 mg tablets.

Your doctor will determine the appropriate dose based on your individual needs and medical conditions.

Usage:

Sildenafil, widely known by the brand name Viagra, is a prescription medication that belongs to a class of drugs called PDE5 inhibitors. Its primary use is to treat Erectile Dysfunction (ED) in men by increasing blood flow to the penis during sexual stimulation. For ED, it is taken as needed, usually about an hour before activity, and should not be taken more than once per day.

In a lower-dose formulation (marketed as Revatio), sildenafil is also used to treat Pulmonary Arterial Hypertension (PAH), a serious condition involving high blood pressure in the lung arteries, for which it is taken regularly, multiple times a day.

Mechanism of Action:
Viagra (sildenafil) is a Phosphodiesterase-5 (PDE5) inhibitor that functions as a crucial aid in the natural erection process, specifically requiring sexual stimulation to be effective. When a man is sexually aroused, his body produces cyclic Guanosine Monophosphate (cGMP). This chemical signals the blood vessels in the penis to relax and widen, resulting in increased blood flow and an erection. The PDE5 enzyme is typically present to break down cGMP, thereby terminating the erection. By inhibiting the PDE5 enzyme, sildenafil prevents the rapid degradation of cGMP, thereby prolonging the chemical signal for blood vessel relaxation. This action ensures increased and sustained blood flow to the penile tissues, making it easier to both attain and maintain a firm erection during sexual activity.

Take Viagra exactly as prescribed by your doctor, following the instructions in the product monograph in Canada. Consult your doctor for personalized guidance and safe use.

The information below summarizes some, but not all, potential side effects, risks, and interactions. Before taking Viagra, it is essential to discuss all possible effects, risks, and interactions with your doctor or pharmacist.

Side Effects:

The information below outlines potential side effects of Viagra (sildenafil). It is not an exhaustive list, and individual reactions can vary.

Common side effects – The following are common side effects of Viagra; other side effects may also occur. Contact your doctor promptly if any side effects are persistent, worsening, or concerning, or if you experience any other concerning symptoms.
• Back pain and muscle aches (myalgia)
• Dizziness
• Flushing (redness or warming of the face, neck, or chest)
• Headache
• Indigestion (upset stomach or heartburn)
• Nasal congestion (stuffy nose)
• Nausea
• Vision changes, which can include seeing a slight blue tinge to objects, blurred vision, or increased light sensitivity

Other Potential Side Effects (less common):
• Diarrhea
• Hypotension (low blood pressure), which may cause light-headedness or fainting
• Nosebleeds
• Rash

Serious or rare side effects: These are rare but potentially severe side effects. Seek immediate medical attention or call emergency services if you experience any of the following:
• A sudden decrease or loss of hearing, sometimes with ringing in the ears and dizziness.
• A sudden decrease or loss of vision in one or both eyes.
• Chest pain or other symptoms of a heart attack (like pain spreading to the jaw or shoulder) or stroke, especially during sexual activity.
• Priapism: An erection that is painful or lasts for more than four hours. This can cause permanent damage to the penis if not treated right away.
• Temporary decreased blood flow to parts of the brain (transient ischemic attack)
• Severe Allergic Reaction: Symptoms like swelling of the face, lips, tongue, or throat, or trouble breathing.

Contraindications:

The following is not an exhaustive list of contraindications. Before starting Viagra, it is crucial to discuss all your medical conditions, past and present, and all medications you are taking with your doctor or pharmacist.

Viagra should not be used under the following conditions:
• A known hypersensitivity or allergic reaction to sildenafil or any of its ingredients.
• The risk of severe, life-threatening hypotension (dangerously low blood pressure).
o Nitrates (e.g., nitroglycerin, isosorbide dinitrate, or isosorbide mononitrate) include: Recreational drugs known as "poppers" (alkyl nitrites).
o Soluble Guanylate Cyclase (sGC) Stimulators (e.g., riociguat/Adempas).

Tell your doctor about your medical conditions, past and present, before starting Viagra. This is crucial because certain conditions can affect whether Viagra is right for you. These conditions may include, but are not limited to:
• Anatomical deformity of the penis (such as angulation, cavernosal fibrosis, or Peyronie's disease), as this increases the risk of a prolonged erection (priapism).
• Any medical conditions that predispose you to priapism, such as leukemia, multiple myeloma, or sickle cell anemia.
• Bleeding disorders or an active peptic ulcer.
• Cardiovascular disease, including a history of stroke, heart attack, life-threatening irregular heartbeat, or severe heart failure within the last six months
• Certain severe eye conditions, such as non-arteritic anterior ischemic optic neuropathy (NAION) or retinitis pigmentosa.
• High or low blood pressure that is uncontrolled.
• Impaired kidney function (severe renal impairment).
• Impaired liver function (severe hepatic impairment).

Drug Interactions:

Before taking Viagra, it is essential to discuss all potential risks and interactions with your doctor or pharmacist. For complete and up-to-date information, please visit the patient information from Pfizer at https://labeling.pfizer.com/ShowLabeling.aspx?id=652§ion=ppi.

Provide your doctor with a complete list of all your medications, including prescriptions, over-the-counter drugs, vitamins, and herbal supplements. Viagra may interact with the following:
• Alpha-Blockers (used for high blood pressure or enlarged prostate, e.g., prazosin, doxazosin, tamsulosin): This combination can increase the risk of low blood pressure (hypotension), dizziness, or fainting. Sildenafil should typically be initiated at a low dose after stable alpha-blocker therapy is established.
• Antifungals (e.g., ketoconazole, itraconazole): These medications inhibit the enzyme that breaks down sildenafil, leading to increased drug concentration in the body and a higher risk of side effects.
• Blood Pressure Medications (other classes, e.g., ACE inhibitors, ARBs, Calcium Channel Blockers): Sildenafil's effect of widening blood vessels may be additive with these drugs, potentially causing a greater drop in blood pressure.
• CYP3A4 Inhibitors (e.g., the antibiotic erythromycin, the HIV medication ritonavir): These potent enzyme inhibitors slow the metabolism of sildenafil, raising its levels in the bloodstream and increasing the risk and severity of side effects. A lower dose of sildenafil is often required.
• Grapefruit Juice: This beverage can inhibit the enzyme that processes sildenafil, increasing the drug's concentration in the body and raising the risk of side effects. It is generally advised to avoid or limit consumption.
• Nitrates (e.g., nitroglycerin, isosorbide dinitrate, or isosorbide mononitrate, including street drugs known as "poppers"): This combination is strictly contraindicated (must never be used) because it can cause a severe, life-threatening drop in blood pressure.
• Other PDE5 Inhibitors (e.g., tadalafil, vardenafil, avanafil): Combining these medications can dangerously amplify their effects, leading to a higher risk of severe side effects like profound low blood pressure and prolonged erection (priapism). This combination is strongly discouraged.
• Soluble Guanylate Cyclase (sGC) Stimulators (e.g., riociguat): This combination is strictly contraindicated (must never be used) as it can lead to a dangerously severe drop in blood pressure.

Pregnancy and Breastfeeding:

Viagra (sildenafil) is not approved for use in women and is contraindicated for healthy pregnant or breastfeeding mothers. The drug's active ingredient, sildenafil (also sold as Revatio), is a potent vasodilator mainly used to treat erectile dysfunction in men and, for both genders, a serious condition called pulmonary arterial hypertension (high blood pressure in the lungs). If a woman is pregnant or breastfeeding, doctors will only prescribe sildenafil to treat life-threatening pulmonary hypertension, where the benefits outweigh the minimal risks; specialists strictly manage this treatment. Otherwise, women should avoid taking sildenafil during pregnancy or while nursing.

Use in Children:

Viagra is not used in children for erectile dysfunction and has no role in healthy children. Its only use in the pediatric population is to treat the severe, life-threatening condition known as Pulmonary Arterial Hypertension (PAH), which is high blood pressure in the arteries of the lungs. Although sildenafil is a standard PAH treatment, medical safety warnings exist regarding high doses, which have been associated with increased risk in children. Therefore, sildenafil is only prescribed by specialists in carefully calculated, weight-based doses for pediatric patients with PAH, requiring close, continuous medical supervision.

Use in Older Adults:

Viagra (sildenafil) is effective for treating Erectile Dysfunction (ED) in older men, but its use necessitates specific safety considerations. As men age, the liver and kidneys often become less efficient at clearing sildenafil and its active metabolite from the bloodstream, resulting in higher and more prolonged plasma concentrations. To mitigate the increased risk of dose-related side effects such as hypotension (low blood pressure), dizziness, and flushing, the generally recommended starting dose for adults over 65 is the lowest strength, 25 mg. This cautious dosing strategy allows physicians to carefully titrate the dosage based on the patient’s individual efficacy and tolerability. Furthermore, sildenafil remains absolutely contraindicated for patients taking nitrate medications for chest pain.

Frequently Asked Questions about Viagra at Canada Pharmacy Online:

Why is Viagra more affordable in Canada than in the United States?

Prescription drug prices, including Viagra, are generally lower in Canada than in the US due to a combination of factors, primarily government price regulations, differing market dynamics, and other economic considerations. In Canada, provincial and federal governments negotiate drug prices with pharmaceutical companies, which often results in lower costs compared to the U.S., where market forces play a more significant role. For more information, see the FAQs on Prescription Drug importation from Kaiser Family Foundation (KFF): https://www.kff.org/health-costs/issue-brief/faqs-on-prescription-drug-importation/.

How much is the shipping?

Our shipping fee is a flat rate of $10.00 per order. Our pharmacy is dedicated to providing you with the lowest prices on high-quality products.

How do I place an order with your pharmacy?

Ordering from us is very simple. You can purchase online or call Customer Service at 1866.920.3784 for more information or to learn about the ordering process. Visit our How to Order page for details.

How to take Viagra for the best results?

You can take Viagra 30 minutes to up to 4 hours before sexual activity on an empty stomach, but it shouldn’t be taken more than once daily.

Can women take Viagra?

Viagra is approved to treat ED in men, but it's not approved for use in women. Addyi is an approved drug also known as “female Viagra” intended to increase a woman's libido.

At what age does a man need Viagra?

Erectile dysfunction can occur at any age. The study demonstrated that ED is increasingly prevalent with age: approximately 40% of men are affected at age 40, and nearly 70% of men are affected at age 70.

Can you cut or split a Viagra tablet?

Yes, Viagra and the generic Sildenafil products can be safely cut or split in half. Always consult your physician or pharmacist before splitting your sildenafil tablet. (Is it Safe to Split a Viagra Tablet?).

Can I buy Viagra over the counter from you?

No, Viagra requires a valid prescription from your doctor. We do not sell this product without a valid prescription.

What is the difference between Viagra 50 mg and 100 mg?

The difference in dosage represents the amount of active ingredient(s) present in the drug.

How long does Viagra last?

Viagra usually lasts between two and three hours before its effects start to diminish. It can last up to five hours or longer, depending on your dosage, your body's metabolism, and other factors (source).

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The information on this page is sourced from independent third parties contracted by CanadaPharmacyOnline. While we cannot guarantee its medical accuracy, we strongly recommend consulting a healthcare professional for personalized advice regarding medications or medical conditions.

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