Tadalafil
CIALIS
Pronunciation: ta-DA-la-fil (see-AL-is)
“See Alice, the Tadophile”
What it isPDE5 inhibitor; erectile dysfunction, benign prostatic hyperplasia and pulmonary arterial hypertension.
Why this oneIts unusually long action supports either on-demand or continuous erectile-dysfunction treatment and also improves BPH symptoms.
What limits itNitrates can cause fatal hypotension and remain unsafe long after a dose; CYP3A4 inhibitors prolong exposure. Back pain is characteristic.
Pearls
- BPH: maximal symptom relief within about a month.
- Good BPH choice when other drugs' sexual adverse effects are a concern.
- Rare sudden vision or hearing loss; priapism needs urgent care.
Tadalafil prescription history
Animated chart of estimated U.S. prescriptions per year, BPH meds (1987–2026). Tadalafil enters in 2003 (estimated).
FDA-approved for
- erectile dysfunction (2003)
- BPH (2011)
Off-label
- Raynaud phenomenon
Principal riskFatal hypotension with nitrates, for up to 48 hours
Classes and tags
Clinical profile
Legacy pregnancy categoryUnknown / historical label unavailable
Defining liabilityGenerally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.
FDA label
Read the full label on DailyMed ↗
NO BOXED WARNINGS
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Erectile dysfunction — as needed | Adult men | 10 mg PRN before sexual activity | 5–20 mg PRN (by efficacy/tolerability) | 20 mg, not more than once per day |
| Erectile dysfunction — once daily | Adult men | 2.5 mg QD | 2.5–5 mg QD | 5 mg QD |
| BPH signs and symptoms | Adult men | 5 mg QD | 5 mg QD | 5 mg QD |
| ED + BPH | Adult men | 5 mg QD | 5 mg QD | 5 mg QD |
Renal PRN use: CrCl 30–50 start 5 mg ≤ once/day, max 10 mg ≤ once per 48 h; CrCl <30 or HD max 5 mg ≤ once per 72 h. Once daily ED: CrCl <30 or HD not recommended. Once daily BPH or ED/BPH: CrCl 30–50 start 2.5 mg, may increase to 5 mg; CrCl <30 or HD not recommended
Hepatic PRN use: Child-Pugh A/B max 10 mg once per day; once daily use: caution in Child-Pugh A/B (not extensively evaluated); Child-Pugh C: not recommended
Instructions
- Do not split tablets; take entire dose
- Take with or without food
- PRN: take before anticipated sexual activity (effect up to 36 h); once daily: same time each day, regardless of sexual activity
- Potent CYP3A4 inhibitors (e.g., ketoconazole, ritonavir): PRN max 10 mg, not more than once every 72 h; once daily max 2.5 mg
- Alpha-blockers: ED — be stable on alpha-blocker, start at lowest dose; BPH — combination not recommended (stop alpha-blocker at least one day before starting once daily CIALIS)
- BPH started together with finasteride: 5 mg QD for up to 26 weeks
Available strengths
- tab 2.5, 5, 10, 20, 40 mg
- susp 20 mg/5 mL
Contraindications
- Any form of organic nitrate, regular or intermittent (potentiates hypotension); if nitrate medically necessary, ≥48 h after last dose under supervision
- Concomitant guanylate cyclase stimulators (e.g., riociguat)
Cautions
- Cardiovascular: avoid if sexual activity inadvisable; not recommended after MI within 90 days, unstable angina, NYHA Class 2+ HF within 6 months, uncontrolled arrhythmia/BP, stroke within 6 months
- Once daily use gives continuous levels — consider interaction potential
- Prolonged erection >4 h / priapism — seek emergency care
- Eye: NAION — stop if sudden vision loss; retinitis pigmentosa not recommended
- Sudden decrease or loss of hearing
- Alpha-blockers and antihypertensives — additive hypotension
- Renal impairment — dose limits
- Hepatic impairment — dose limits
- Alcohol (≥5 units) — orthostatic hypotension
- Potent CYP3A4 inhibitors — dose limits
- Do not combine with other PDE5 inhibitors (incl. ADCIRCA) or ED therapies
- Bleeding disorders / active peptic ulcer — risk-benefit caution
- No protection against sexually transmitted diseases
- BPH: consider other urological conditions, incl. prostate cancer
Adverse reactions
- Headache
- Dyspepsia
- Back pain
- Myalgia
- Nasal congestion
- Flushing
- Pain in limb
Pregnancy Not indicated in females; no human data; no adverse developmental effects in rats/mice at up to 11× MRHD
Lactation Not indicated in females; no human milk data; present in rat milk at ~2.4× plasma
Cost
| Strength | #/mo | generic $/mo | CostPlus | |
|---|---|---|---|---|
| 2.5 mg | tab | 30 qd | $3.38 | offered |
| 5 mg | tab | 30 qd | $3.10 | offered |
| 10 mg | tab | 30 qd | $4.60 | offered |
| 20 mg | tab | 30 qd | $5.01 | offered |
| 40 mg | tab | 30 qd | not offered |
Other forms: Tadalafil (PAH) (ADCIRCA)
Generic entry2018
Open Tadalafil in the interactive console ↗
Memory aids: interaction avatars
Open Tadalafil in the interactive console ↗
Self-check
- What permits both on-demand and continuous tadalafil treatment?
Its unusually long action. - Which drug class can cause fatal hypotension with tadalafil?
Nitrates.