Tadalafil

Tadalafil is a prescription oral medication used to treat erectile dysfunction (ED) in adult men. It belongs to the phosphodiesterase type 5 (PDE5) inhibitor drug class, which works by relaxing blood vessels and increasing blood flow to penile tissue during sexual stimulation.

Men choose it for one main reason: a single dose lasts up to 36 hours, far longer than most alternatives. Generic versions are widely available and contain the same active compound as brand-name Cialis.

What Is Tadalafil?

Tadalafil is a PDE5 inhibitor. It was originally developed and marketed under the brand name Cialis by Eli Lilly. After the patent expired in 2018, generic versions became widely available at a fraction of the original cost.

The drug is FDA-approved for three indications: erectile dysfunction, benign prostatic hyperplasia (BPH), and pulmonary arterial hypertension (PAH).

All Vidalista formulations contain tadalafil as the active ingredient and are considered bioequivalent to brand Cialis. Available strengths on Staminite: 10 mg, 20 mg, 60 mg, 80 mg, and Vidalista Black 80 mg.

Uses of Tadalafil

Erectile Dysfunction (ED)

Tadalafil is most commonly prescribed for ED, a condition where a man cannot get or maintain an erection firm enough for sexual activity. It does not increase sexual desire. It only supports the physical mechanism of an erection when the man is sexually aroused.

It can be taken on-demand (10 mg or 20 mg, as needed) or as a low-dose daily treatment (2.5 mg or 5 mg). Both approaches are effective. The on-demand option suits men who prefer not to take medication every day.

Benign Prostatic Hyperplasia (BPH)

BPH is an enlarged prostate gland. It causes urinary symptoms including weak urine flow, frequent urination at night, and difficulty starting urination. Tadalafil 5 mg daily is FDA-approved for BPH. It relaxes smooth muscle in the prostate and bladder neck, which reduces these urinary symptoms over time.

This makes it particularly useful for older men dealing with both ED and BPH simultaneously.

Erectile Dysfunction + BPH

Tadalafil is the only ED medication approved by the FDA to treat both ED and BPH with a single daily dose. Men who take 5 mg daily get relief from BPH symptoms and continuous support for erections — without needing to time a dose.

Off-Label Uses

Tadalafil (under the brand name Adcirca) is also used to treat pulmonary arterial hypertension (PAH), a type of high blood pressure in the arteries supplying the lungs. This is an approved use, not off-label.

Some doctors prescribe it off-label for Raynaud’s phenomenon, a condition causing reduced blood flow to fingers and toes in cold conditions. This use is not FDA-approved and should only be considered under direct medical supervision.

Recommended Dosage Guide

Strength	Use Case	Timing	Notes
2.5 mg	Daily (ED / BPH)	Same time daily	Lowest maintenance dose; good starting point
5 mg	Daily (ED + BPH)	Same time daily	FDA-approved for both ED and BPH
10 mg	On-demand (ED)	30–60 min before	Starting on-demand dose; good for first-time users
20 mg	On-demand (ED)	30–60 min before	Most commonly prescribed on-demand dose

For Erectile Dysfunction (On-Demand)

Starting dose: 10 mg, taken 30 to 60 minutes before sexual activity.

Maximum dose: 20 mg per day. Do not exceed this.

Frequency: No more than once in a 24-hour period. Avoid taking on several consecutive days.

With or without food: Food does not significantly affect absorption. High-fat meals may slightly delay onset.

For Daily Use

Dose: 2.5 mg to 5 mg once daily at the same time each day.

No timing required: Daily dosing builds a steady plasma level, so there is no need to plan around sexual activity.

Missed dose: If you miss a dose and it is close to the time of your next scheduled dose, skip it. Never take two doses in one day.

For Benign Prostatic Hyperplasia (BPH)

Dose: 5 mg once daily. The same dose used for daily ED treatment.

Onset: BPH symptom relief may take several weeks of consistent daily dosing to become noticeable.

Important Dosage Notes

• Men with kidney impairment (creatinine clearance 30–50 mL/min): maximum 10 mg on-demand, not more than once every 48 hours
• Men with severe kidney impairment (creatinine clearance below 30 mL/min): daily tadalafil is not recommended
• Men with mild to moderate liver impairment: maximum 10 mg on-demand; daily use not studied and not recommended for severe hepatic impairment
• Men taking strong CYP3A4 inhibitors (e.g. ketoconazole, ritonavir): maximum 10 mg on-demand or 2.5 mg daily
• Doses above 20 mg (e.g. 40 mg, 60 mg, 80 mg) are not FDA-approved standard doses. They exist as generic variants and should only be considered under direct medical guidance

Side Effects of Tadalafil

Common Side Effects

These occur in more than 1 in 10 users and are generally mild. They tend to reduce with continued use:

• Headache — most frequently reported side effect
• Facial flushing — warmth or redness in the face
• Indigestion or heartburn
• Nasal congestion or runny nose
• Back pain or muscle aches — more common with tadalafil than with other PDE5 inhibitors
• Dizziness, especially when standing up quickly

These effects usually resolve within a few hours without treatment.

Serious Side Effects

These are uncommon but require immediate medical attention:

• Sudden vision loss in one or both eyes (non-arteritic anterior ischemic optic neuropathy — NAION). Stop tadalafil immediately and seek emergency care
• Sudden hearing loss or ringing in the ears (tinnitus). Discontinue and consult a doctor immediately
• Priapism — a painful erection lasting more than 4 hours. This is a medical emergency. Seek care immediately to avoid permanent tissue damage
• Severe drop in blood pressure, particularly if combined with nitrates or alpha-blockers
• Chest pain during sexual activity — stop and seek emergency care

Rare Side Effects

• Stevens-Johnson syndrome (severe skin reaction) — rare but serious hypersensitivity reaction
• Exfoliative dermatitis — rare skin condition involving widespread skin shedding
• Vision changes including blurred vision or colour distortion
• Seizures — very rare, reported in post-marketing surveillance

If you experience any side effect that is persistent, severe, or unusual, contact your healthcare provider promptly.

Drug Interactions

Tadalafil stays in the body for up to 17.5 hours (half-life) and can remain detectable for several days. This means interactions can occur even if you did not take tadalafil and another medication on the same day.

Always give your prescriber a complete list of all medications, supplements, and herbal products you are currently taking.

Drug / Substance	Examples	Risk / What Happens
Nitrates	Nitroglycerin, isosorbide mononitrate, isosorbide dinitrate	CONTRAINDICATED — severe blood pressure drop, risk of fainting or cardiac event
sGC Stimulators	Riociguat (Adempas)	CONTRAINDICATED — dangerous hypotension
Alpha-blockers	Tamsulosin, terazosin, doxazosin, alfuzosin	Significant blood pressure drop; dose adjustment may be required
Blood pressure medications	Lisinopril, amlodipine, losartan	Additive BP lowering; monitor for dizziness and lightheadedness
Other PDE5 inhibitors	Sildenafil, vardenafil, avanafil	Avoid combining — excessive BP drop and increased side effects
CYP3A4 inhibitors	Ketoconazole, itraconazole, ritonavir, erythromycin	Increases tadalafil blood levels; max dose reduced to 10 mg (on-demand) or 2.5 mg (daily)
CYP3A4 inducers	Rifampin, carbamazepine, phenytoin, phenobarbital, St. John’s Wort	Reduces tadalafil effectiveness; may need dose adjustment
Alcohol	Beer, wine, spirits	Both lower blood pressure; heavy drinking increases dizziness, fainting, reduced effectiveness
Grapefruit / juice	Fresh grapefruit, grapefruit juice	Inhibits CYP3A4 enzyme; may raise tadalafil levels unpredictably

Key point on CYP3A4 interactions: Tadalafil is primarily metabolised by the CYP3A4 liver enzyme. Drugs that inhibit this enzyme (e.g. ketoconazole, ritonavir) increase tadalafil blood levels and side effect risk. Drugs that induce it (e.g. rifampin, carbamazepine) reduce tadalafil effectiveness. Your doctor will adjust your dose accordingly.

Advantages

• Duration up to 36 hours — the longest of any FDA-approved PDE5 inhibitor
• Flexible timing — no need to take it immediately before sex
• Not significantly affected by food or high-fat meals
• Dual approval — treats both ED and BPH with a single daily dose
• Daily dosing option eliminates the need to plan around sexual activity
• Generic availability makes it significantly more affordable than brand Cialis
• Well-studied safety profile with decades of clinical use

Disadvantages

• Back pain and muscle aches are more commonly reported with tadalafil than with sildenafil or vardenafil
• Longer half-life means it stays in the system longer, which can prolong side effects if they occur
• Not suitable for men on nitrates — strict contraindication with no workaround
• Higher-strength generics (60 mg, 80 mg) are not FDA-approved standard doses and carry greater risk
• Grapefruit interaction requires dietary consideration
• Requires a valid prescription — cannot be purchased over the counter
• Daily dosing requires consistent adherence to maintain steady plasma levels

How to Use Tadalafil Safely

Follow these clinical guidelines to reduce your risk of side effects and interactions:

• Take only the prescribed dose. Do not increase it without consulting your doctor
• For on-demand use, take 30 to 60 minutes before planned sexual activity — not more than once per day
• For daily use, take it at the same time every day to maintain consistent blood levels
• Limit alcohol to 1 to 2 standard drinks. Avoid heavy drinking on the same day
• Avoid grapefruit and grapefruit juice while on tadalafil
• Do not combine with any nitrate medication, including recreational drugs like amyl nitrite (poppers)
• Tell every doctor and pharmacist you see that you are taking tadalafil, including before any surgical procedure
• If you experience an erection lasting more than 4 hours, seek emergency care immediately
• Store tablets at room temperature, away from moisture and direct sunlight

Who Should Not Take Tadalafil?

Do not take tadalafil if any of the following apply to you:

• You are currently using nitrate medications in any form (tablets, patches, sprays, or recreational nitrites)
• You are using riociguat (Adempas) or other sGC stimulators
• You have had a heart attack or stroke within the last 90 days
• You have uncontrolled high blood pressure or very low blood pressure (below 90/50 mmHg)
• You have severe liver impairment (Child-Pugh class C)
• You have severe kidney disease requiring dialysis
• You have a known hypersensitivity or allergic reaction to tadalafil
• You have a condition that makes sexual activity inadvisable, as determined by your doctor
• You have non-arteritic anterior ischemic optic neuropathy (NAION) — a history of sudden vision loss

Men with moderate liver or kidney impairment, men taking alpha-blockers, and men over 70 should discuss dose adjustments with their doctor before use.

Frequently Asked Questions

How long does tadalafil take to work?

It typically starts working within 30 to 45 minutes. Most men reach peak blood concentration around 2 hours after taking the dose. Sexual stimulation is required for it to take effect.

How long does tadalafil last?

A single on-demand dose can remain effective for up to 36 hours. This is significantly longer than sildenafil (4–6 hours) or vardenafil (4–6 hours). The actual duration varies between individuals based on metabolism, age, and dose.

Can I take tadalafil daily?

Yes, with a prescription. The daily dose is 2.5 mg or 5 mg, taken at the same time each day. It builds a consistent level in your system so you do not need to plan around sexual activity. The 5 mg dose is also approved for BPH.

What is the difference between 10 mg and 20 mg?

10 mg is the starting on-demand dose, suited for first-time users or men who are sensitive to higher doses. 20 mg is the standard maximum on-demand dose and the most commonly prescribed strength. If 10 mg works well, there is no reason to increase to 20 mg.

Does tadalafil work without sexual stimulation?

No. Tadalafil only works in response to sexual arousal. It relaxes blood vessels to support blood flow but does not produce an erection on its own. Without stimulation, no effect occurs.

Can I drink alcohol while taking tadalafil?

Moderate alcohol (1 to 2 standard drinks) is generally acceptable. Both alcohol and tadalafil lower blood pressure, so combining them in large amounts increases the risk of dizziness, lightheadedness, and fainting. Avoid heavy drinking on the same day.

Is tadalafil better than sildenafil?

Neither is universally better. Tadalafil lasts longer (up to 36 hours vs 4–6 hours) and is less affected by food. Sildenafil tends to have faster onset in some men. The right choice depends on your lifestyle, how often you are sexually active, and how you respond to each drug. Discuss the options with your doctor.

Medical Disclaimer

The information on this page is for general educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a licensed healthcare provider before starting, stopping, or adjusting any prescription medication.

Tadalafil is a prescription-only medication in the USA and Australia. Staminite.com does not dispense it without a valid prescription. Individual responses to medication vary, and only a qualified provider can determine whether tadalafil is appropriate for your specific health situation.

References

MedlinePlus (U.S. National Library of Medicine) — Tadalafil 

Mayo Clinic — Tadalafil (Oral Route): Description and Brand Names