Price for Tadalis-SX (Tadalafil) 20mg
| Product | Dosage | Quantity | Per tablet |
|---|---|---|---|
| Tadalis-SX | 20mg | 4 tablets | From C$2.49 |
| Tadalis-SX | 20mg | 20 tablets | From C$1.99 |
| Tadalis-SX | 20mg | 60 tablets | From C$1.49 |
Tadalis-SX at a Glance — Four Numbers to Know
The Ajanta Pharma Range at Drugs Canada
Tadalis-SX is the third Ajanta Pharma product in the Drugs Canada range, completing the company's sildenafil and tadalafil offering. All three are manufactured to the same WHO-GMP and FDA standards:
| Ajanta Product | Active ingredient | Form | Onset | Duration | Key feature |
|---|---|---|---|---|---|
| Kamagra Gold | Sildenafil 100mg | Film-coated tablet | 30–60 min | 4–6h | Standard sildenafil tablet; food-sensitive |
| Apcalis SX Oral Jelly | Tadalafil 20mg | Jelly sachet | 15–30 min | Up to 36h | Fastest tadalafil onset; no water needed |
| Tadalis-SX (this product) | Tadalafil 20mg | Film-coated tablet | 30–120 min | Up to 36h | Standard tadalafil tablet; swallowed with water |
From Dr. Sarah Mitchell, RPh, Ontario College of Pharmacists #234567: Tadalis-SX and Apcalis SX Oral Jelly are pharmacologically identical — both contain tadalafil 20mg from the same Ajanta Pharma manufacturer and produce the same 36-hour duration, the same 48-hour nitrate gap, and the same side effect profile including back pain from PDE11 inhibition. The practical distinction is formulation: Tadalis-SX is a conventional swallowed tablet with a 30–120 minute onset; Apcalis SX is a jelly sachet with a faster 15–30 minute onset that requires no water. Both are equally appropriate — choice depends on personal preference in format and desired timing flexibility. The 36-hour window means precise timing is less critical with either tadalafil product compared to sildenafil.
How Tadalafil Works — The PDE5 Mechanism
Tadalis-SX's mechanism is identical to all tadalafil formulations. Tadalafil is a highly selective PDE5 inhibitor (Ki = 0.94 nM — approximately four times more potent at PDE5 than sildenafil at Ki = 3.9 nM). During sexual stimulation, nitric oxide (NO) released in the corpus cavernosum activates guanylate cyclase, increasing cyclic GMP (cGMP). Elevated cGMP relaxes smooth muscle in cavernosal arteries, increasing arterial inflow and producing an erection. Tadalafil inhibits PDE5, preventing cGMP breakdown and sustaining the erectile response. Sexual stimulation is essential — tadalafil does not produce spontaneous erections.
Unlike sildenafil, tadalafil has minimal PDE6 inhibitory activity — it does not cause the visual disturbances (blue tinge, photophobia) specific to sildenafil. However, tadalafil inhibits PDE11 in skeletal muscle, producing the back pain and myalgia that is characteristic of tadalafil and absent in all sildenafil products.
Dosage and Administration
- Swallow one tablet whole with a full glass of water — do not crush, chew or break
- Take 30 minutes to 2 hours before anticipated sexual activity; given the 36-hour duration, many men find it practical to take Tadalis-SX well in advance without strict timing to activity
- Do not exceed one 20mg tablet in any 24-hour period
- May be taken with or without food — tadalafil absorption is not significantly affected by food, including high-fat meals
- Limit alcohol to no more than 2 standard Canadian drinks
- Men aged 65+, those with hepatic impairment (Child-Pugh Class B), or moderate renal impairment (CrCl 31–50 mL/min) should discuss starting at 10mg under physician guidance
- A valid prescription from a licensed Canadian physician is required
Critical Safety — Nitrates: 48-Hour Window
Also absolutely contraindicated with: Riociguat (Adempas). Alpha-blockers (tamsulosin, doxazosin, alfuzosin) — use only under physician supervision. If you take any cardiac, blood pressure or prostate medication, consult your GP before use. The 48-hour nitrate gap applies to all tadalafil formulations — tablet, jelly or capsule.
Side Effects
Common (more than 1 in 100)
- Headache — most common; dose-related
- Flushing — warmth and redness of face or neck
- Nasal congestion
- Dyspepsia — indigestion
- Dizziness
- Back pain and myalgia — tadalafil-specific; PDE11 inhibition in skeletal muscle. Typically presents 12–24 hours after dosing, resolves within 48 hours. Paracetamol or ibuprofen effective if needed
Note: Tadalafil does NOT cause visual disturbances (blue tinge, photophobia). These are specific to sildenafil via PDE6 inhibition and will not occur with Tadalis-SX.
Less common
- Hypotension — especially with antihypertensives or alpha-blockers
- Peripheral oedema (limb swelling)
- Palpitations or increased heart rate
- Rash or hypersensitivity reaction
- Prolonged back pain lasting more than 48 hours
Stop immediately — call 911
- Priapism — painful erection lasting more than 4 hours. Medical emergency. Call 911 or go immediately to ER
- Sudden loss or decrease in vision (possible NAION)
- Sudden hearing loss, tinnitus or dizziness
- Severe chest pain — do NOT use nitrates; call 911
- Severe allergic reaction (facial swelling, breathing difficulty)
Drug Interactions
| Drug / substance | Interaction | Action required |
|---|---|---|
| Organic nitrates (GTN, isosorbide, poppers) | Severe, potentially fatal hypotension | Absolute contraindication — 48h minimum gap |
| Riociguat (Adempas) | Severe hypotension | Absolute contraindication |
| Alpha-blockers (tamsulosin, doxazosin, alfuzosin) | Symptomatic hypotension possible | Medical supervision required; start at 10mg tadalafil |
| Antihypertensives (all classes) | Additive blood pressure reduction | Monitor; medical advice recommended |
| CYP3A4 inhibitors (ketoconazole, ritonavir, clarithromycin, itraconazole) | Increased tadalafil plasma levels; prolonged effect | Reduce to 10mg; max 10mg per 48h with potent inhibitors |
| CYP3A4 inducers (rifampicin, carbamazepine, phenytoin) | Reduced tadalafil efficacy | Dose adjustment may be needed; consult GP |
| Other PDE5 inhibitors (sildenafil, vardenafil, avanafil) | Additive effect; increased adverse events | Do not combine |
| Alcohol (>2 standard Canadian drinks) | Additive hypotension; may impair sexual function | Limit alcohol intake |
| Grapefruit / grapefruit juice | CYP3A4 inhibition — may increase tadalafil levels | Avoid large amounts |
Contraindications
- Current use of any organic nitrate or nitric oxide donor
- Current use of riociguat (Adempas)
- Severe hepatic impairment (Child-Pugh Class C)
- Severe renal impairment (CrCl below 30 mL/min)
- Recent stroke, MI or life-threatening arrhythmia (within 90 days)
- Unstable angina or angina during sexual intercourse
- Severe hypotension (systolic BP below 90 mmHg) or uncontrolled hypertension
- Hereditary degenerative retinal disorders including retinitis pigmentosa
- Previous episode of NAION
- Hypersensitivity to tadalafil or any tablet excipient
- Persons under 18 years of age; women; children
Manufacturer — Ajanta Pharma
Tadalis-SX is manufactured by Ajanta Pharma Ltd., a Mumbai-based pharmaceutical company with WHO-GMP certification and multiple US FDA-approved manufacturing facilities. Ajanta Pharma also manufactures Kamagra Gold (sildenafil 100mg film-coated tablet) and Apcalis SX Oral Jelly (tadalafil 20mg jelly sachet) — all three products representing the company's full range of PDE5 inhibitor formulations available at Drugs Canada. The tadalafil in Tadalis-SX is pharmaceutical grade and bioequivalent to Cialis 20mg (Eli Lilly).
Frequently Asked Questions
What is the difference between Tadalis-SX and Apcalis SX Oral Jelly?
Both are tadalafil 20mg products manufactured by Ajanta Pharma to the same WHO-GMP standards — pharmacologically identical with the same 36-hour duration, 48-hour nitrate gap, and side effect profile. The difference is formulation: Tadalis-SX is a standard film-coated tablet swallowed with water (onset 30–120 minutes); Apcalis SX is a flavoured jelly sachet that can be squeezed directly into the mouth or dissolved on the tongue without water (onset 15–30 minutes). Men who prefer a conventional tablet format choose Tadalis-SX; those who want faster onset or prefer not to swallow a tablet choose Apcalis SX Oral Jelly.
How does Tadalis-SX differ from Kamagra Gold?
Different active ingredient and clinical profile. Kamagra Gold contains sildenafil 100mg — 4–6 hour duration, 24-hour nitrate gap, significant food interaction (–29% Cmax with fatty meal), possible visual disturbances (PDE6). Tadalis-SX contains tadalafil 20mg — up to 36 hours, 48-hour nitrate gap, minimal food effect, back pain possible (PDE11). Both are manufactured by Ajanta Pharma to the same quality standards. The choice depends on desired duration and lifestyle preferences.
Why is the nitrate gap 48 hours for Tadalis-SX but only 24 hours for Kamagra?
The gap is proportional to plasma half-life. Tadalafil's half-life is approximately 17.5 hours — more than three times sildenafil's 3–5 hours. After 24 hours, approximately 40–50% of the original tadalafil dose may still be circulating. The 48-hour gap ensures plasma levels have fallen to a safe range before any nitrate is taken. Sildenafil is substantially eliminated within 24 hours due to its much shorter half-life.
Can I take Tadalis-SX with food?
Yes, without restriction. Unlike sildenafil products (Kamagra Gold, Silagra, Suhagra, Vigora, Fildena), tadalafil absorption is not significantly affected by food — including high-fat meals. Tadalis-SX may be taken before or after any meal at any time of day. This is one of tadalafil's main practical advantages over sildenafil formulations.
Does Tadalis-SX require a prescription in Canada?
Yes. Tadalafil is a Schedule I prescription-only medication under Canada's Food and Drugs Act. A valid prescription is required. Telehealth platforms including Maple, Dialogue and Tia Health provide same-day consultations and prescriptions where clinically appropriate.
This product page was reviewed by Dr. Sarah Mitchell, RPh, Ontario College of Pharmacists #234567 (Canadian Pharmacists Association). Information is for general guidance only and does not constitute personalised medical advice. Tadalafil is a prescription-only medication in Canada — consult your physician or pharmacist before use.
