Buy Cialis (Tadalafil) — Online Prescription
Tadalafil — sold as Cialis, and as a far less expensive generic since 2018 — is a prescription-only PDE5 inhibitor known for lasting up to 36 hours. Here's daily vs. as-needed dosing, how it compares to Viagra, what it actually treats, and real pricing.
Medically reviewed Medically reviewed by Sabrina Griswold, Pharm.D. — NPI 1821451063 · Last updated 2026-08-31
| Active ingredient | Tadalafil |
|---|---|
| Dosage form | Tablet (2.5mg, 5mg, 10mg, 20mg) |
| Administration route | Oral |
Class: Phosphodiesterase 5 Inhibitor [EPC]
Indications: 1 INDICATIONS AND USAGE CIALIS ® is a phosphodiesterase 5 (PDE5) inhibitor indicated for the treatment of: erectile dysfunction (ED) ( 1.1 ) the signs and symptoms of benign prostatic hyperplasia (BPH) ( 1.2 ) ED and the signs and symptoms of BPH (ED/BPH) ( 1.3 ) If CIALIS is used with finasteride to initiate BPH treatment, such use is recommended for up to 26 weeks ( 1.4 ). 1.1 Erectile Dysfunction CIALIS ® is indicated for the treatment of erectile dysfunction (ED). 1.2 Benign Prostatic Hyperp…
Contraindications: 4 CONTRAINDICATIONS Administration of CIALIS to patients using any form of organic nitrate is contraindicated. CIALIS was shown to potentiate the hypotensive effect of nitrates ( 4.1 ). History of known serious hypersensitivity reaction to CIALIS or ADCIRCA ® ( 4.2 ). Administration with guanylate cyclase (GC) stimulators, such as riociguat ( 4.3 ). 4.1 Nitrates Administration of CIALIS to patients who are using any form of organic nitrate, either regularly and/or intermittently, is contraindica…
openFDA label data — Updated 2026-09-02No, Cialis (tadalafil) is not available over the counter in the US — prescription-only, brand and generic alike. Its signature feature is duration: effects can last up to 36 hours, far longer than Viagra's 4–5 hours, which is why it's the only ED medication commonly prescribed as a low daily dose instead of just as-needed. Generic tadalafil has been widely available since 2018 and is typically far less expensive than brand-name Cialis.
Is Cialis available over the counter?
No. Tadalafil — brand name Cialis, and available as a far less expensive generic — requires a prescription in the United States, in every dose and for every approved use. A prescriber needs to evaluate you first, primarily to rule out a dangerous interaction with nitrate medications and confirm your cardiovascular health can tolerate sexual activity.
- Telehealth — many services evaluate and send a prescription to your pharmacy same-day
- Your primary care provider or a urologist
- Ask us — we can often coordinate with your prescriber's office
- Any site offering tadalafil with no prescription or medical evaluation
- "Herbal" or supplement products claiming a Cialis-like effect
- Unusually cheap pricing with no pharmacy license or address listed
ED medications are among the most commonly seized categories of counterfeit drugs by US Customs and the FDA — counterfeit product may contain the wrong dose, no active ingredient, or undisclosed and dangerous additional drugs. See the FDA's BeSafeRx guidance on identifying a legitimate online pharmacy.
What tadalafil actually treats
Tadalafil has three separate FDA approvals, under two different brand names:
| Brand | Approved use | Dosing pattern |
|---|---|---|
| Cialis | Erectile dysfunction (ED) | As-needed (5–20 mg) or daily (2.5–5 mg) |
| Cialis | Benign prostatic hyperplasia (BPH) — enlarged prostate symptoms | Daily only (5 mg) — no as-needed option |
| Cialis | ED and BPH together | Daily (5 mg) |
| Adcirca | Pulmonary arterial hypertension (PAH) | Different regimen, unrelated to sexual activity |
If you're taking tadalafil for BPH, note there's no "as-needed" version — daily dosing is the only FDA-approved schedule for that use, regardless of what dose you may have seen discussed for ED.
Daily Cialis vs. as-needed Cialis
This is tadalafil's signature practical difference from every other ED medication — and the source of a lot of dosage confusion:
5–20 mg
- When to take
- ~30–60 minutes before sexual activity
- Frequency limit
- No more than once in 24 hours
- Best for
- Planned, occasional use
2.5–5 mg
- When to take
- Every day, same time, regardless of activity
- Frequency limit
- Once daily, ongoing
- Best for
- Spontaneity, or BPH (required — no as-needed BPH option)
Never combine the two approaches — taking a daily dose and an as-needed dose in the same period raises your total exposure beyond what's been evaluated as safe. If your current dosing doesn't fit how you actually want to use it, that's worth raising with your prescriber rather than adjusting on your own.
Generic tadalafil vs. brand-name Cialis
Generic tadalafil must meet the same FDA bioequivalence standard as brand-name Cialis — same active ingredient, same doses, same expected effect. There's no clinical reason to pay the brand premium once a generic is available, which it has been in the US since 2018.
The price gap between brand and generic tadalafil is one of the largest of any commonly prescribed medication — see the full price table below by dose and form.
Cialis vs. Viagra (sildenafil)
This is one of the most common questions we get, and there's no universal "better" — it's a fit question:
| Cialis (tadalafil) | Viagra (sildenafil) | |
|---|---|---|
| Duration of effect | Up to 36 hours | ~4–5 hours |
| Dosing pattern | As-needed, or a low daily dose | As-needed only |
| Food effect | Minimal | High-fat meals delay onset |
| Also approved for | BPH, pulmonary arterial hypertension (as Adcirca) | Pulmonary arterial hypertension (as Revatio) |
Never take both together. Combining two PDE5 inhibitors doesn't improve results and increases the risk of side effects, including a dangerous blood pressure drop — especially in combination with nitrates. See our Sildenafil (Viagra) page for the full picture on that option.
Side effects, nitrates, and safety
Common side effects include headache, indigestion, back pain, and muscle aches — the back/muscle pain is more distinctive to tadalafil than to sildenafil, and typically resolves within a day or two. Seek emergency care for an erection lasting longer than 4 hours (priapism) or sudden vision or hearing loss.
Tadalafil can cause a mild blood-pressure drop as part of its normal effect — usually not significant on its own, but this is exactly why your full medication list matters to your prescriber, since certain blood pressure medications can compound the effect.
Cialis for women, and other questions
Tadalafil is not FDA-approved for use in women, and its safety and effectiveness for female sexual dysfunction haven't been established, despite it being a common search. If low sexual desire is the underlying concern, flibanserin (Addyi) is a separate medication FDA-approved specifically for premenopausal women with acquired, generalized low sexual desire — see our Addyi (Flibanserin) page.
Buying, pricing, and savings
- Choose generic. Ask us to fill generic tadalafil unless your prescriber specifically calls for brand-name Cialis — same medication, same FDA standard, meaningfully lower price.
- Daily vs. as-needed changes the math. A low daily dose is a different monthly cost than filling as-needed tablets — ask us to help figure out which is more cost-effective for how you'll actually use it.
- Check the cash price. It's sometimes lower than an insurance copay, especially at higher quantities — ask before assuming insurance is cheapest.
- Speed and discretion. Call us at (860) 522-9289 once you have a prescription and we'll have it ready quickly.
No active shortage reported — No shortage records found for this generic name.
FDA openFDA — Updated 2026-09-02National Average Drug Acquisition Cost (NADAC): $0.180 per tablet (TADALAFIL 20 MG TABLET). This is the average price pharmacies pay wholesalers — not your out-of-pocket cost — published by CMS for pricing transparency.
CMS NADAC — Updated 2026-09-02Cialis (Tadalafil) Prices in the USA
| Dosage | Brand-name avg. price | Generic avg. price |
|---|---|---|
| 2.5 mg (daily) | $450–950 / 30-day supply | $25–60 / 30-day supply |
| 5 mg (daily) | $450–950 / 30-day supply | $30–75 / 30-day supply |
| 10 mg (as needed) | $500–1,000 / 30 tablets | $35–85 / 30 tablets |
| 20 mg (as needed) | $550–1,100 / 30 tablets | $40–95 / 30 tablets |
Frequently asked questions
Can you buy Cialis over the counter, or without a prescription?
No. Tadalafil is prescription-only in the United States in both its brand-name (Cialis) and generic forms — there is no OTC dose. A prescriber needs to rule out interactions, particularly with nitrate medications, before you take it.
What does Cialis actually treat?
The FDA approves tadalafil for erectile dysfunction (ED), for the signs and symptoms of benign prostatic hyperplasia (BPH, or enlarged prostate), and for both conditions together. Under a separate brand name, Adcirca, tadalafil is also FDA-approved to treat pulmonary arterial hypertension (PAH) — a distinct use at a different dose, unrelated to sexual activity.
What's the difference between daily Cialis and as-needed Cialis?
They're the same drug at different doses and schedules. As-needed dosing (5–20 mg) is taken roughly 30–60 minutes before sexual activity, once per day maximum. Daily dosing (2.5–5 mg) is taken every day at the same time regardless of sexual activity, so it's always active — this is also the only option for BPH, which has no as-needed dose. Your prescriber decides which fits your situation.
How is Cialis different from Viagra?
Both are PDE5 inhibitors with a similar safety profile, but tadalafil (Cialis) has a much longer half-life — effects can last up to 36 hours, compared to about 4–5 hours for sildenafil (Viagra). That's why tadalafil is sometimes prescribed for daily, lower-dose use, while sildenafil is as-needed only. Food also affects them differently: a high-fat meal delays sildenafil's onset, while tadalafil is largely unaffected by food.
Can I take Cialis and Viagra together?
No — don't combine two PDE5 inhibitors. Taking tadalafil and sildenafil together doesn't improve effectiveness and increases the risk of side effects, including a dangerous drop in blood pressure, especially if either is combined with nitrates. If one isn't working well for you, that's a conversation for your prescriber, not something to solve by stacking both.
Why can't I take Cialis with nitrate medications?
Tadalafil is contraindicated with any form of organic nitrate (including as-needed nitroglycerin) and with guanylate cyclase stimulators like riociguat — the combination can cause a severe, dangerous drop in blood pressure. Always tell your prescriber and pharmacist about every medication you take, including ones used only occasionally.
Can I drink alcohol with Cialis?
Moderate alcohol isn't strictly prohibited, but both alcohol and tadalafil can lower blood pressure independently, and combining them can increase dizziness, flushing, and headache. Heavy drinking can also impair erectile function on its own, regardless of medication. Keep it light, and ask your pharmacist if you have cardiovascular risk factors.
Does Cialis lower blood pressure?
It can cause a mild drop in blood pressure as part of how it works, which is usually not clinically significant on its own — the real danger is combining it with nitrates or certain blood pressure medications, which can cause a much larger, dangerous drop. Tell your prescriber about all your cardiovascular medications before starting tadalafil.
Can women take Cialis?
Tadalafil is not FDA-approved for use in women, and its safety and effectiveness for female sexual dysfunction haven't been established. If low sexual desire is the concern, flibanserin (Addyi) is a separate medication FDA-approved specifically for that purpose in premenopausal women — see our Addyi page.
How much does Cialis cost, and how do I save?
Generic tadalafil is inexpensive at the wholesale level and typically far cheaper at retail than brand-name Cialis for the identical medication — see the price table below for typical ranges by dose. Always ask us to fill generic unless your prescriber specifies brand-name Cialis, and ask about savings options before assuming insurance is your cheapest route.
Sources
- Cialis (tadalafil) — FDA-approved prescribing information (label) — U.S. Food and Drug Administration
- Adcirca (tadalafil) — FDA-approved prescribing information for pulmonary arterial hypertension — U.S. Food and Drug Administration
- Tadalafil / Cialis price data (average retail cash price) — GoodRx (consumer price reference)
- NADAC (National Average Drug Acquisition Cost) — CMS
- BeSafeRx: Know Your Online Pharmacy — U.S. FDA