Tadalafil
CIALIS
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.
FDA-approved for
- erectile dysfunction (2003)
- BPH (2011)
Off-label
- Raynaud phenomenon
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Pulmonary arterial hypertension (WHO Group 1) | Adults | 40 mg QD | 40 mg QD | 40 mg QD |
| PAH, mild-moderate renal impairment (CrCl 31-80) | Adults | 20 mg QD | 40 mg QD as tolerated | 40 mg QD |
| PAH, on ritonavir ≥1 week | Adults | 20 mg QD | 40 mg QD as tolerated | 40 mg QD |
Renal Mild-moderate (CrCl 31-80): start 20 mg QD; severe (CrCl <30)/on HD: avoid use
Hepatic Mild-moderate (Child-Pugh A/B): consider start 20 mg QD; severe (Child-Pugh C): avoid use
Instructions
- Take with or without food
- Do not divide the 40 mg dose over the day
- On ritonavir: start 20 mg QD; stop tadalafil ≥24 h before starting ritonavir
Contraindications
- Concomitant organic nitrates (any form); do not use nitrates within 48 h of last dose
- Concomitant guanylate cyclase stimulators (e.g., riociguat)
Cautions
- Hypotension (vasodilatory); avoid in pulmonary veno-occlusive disease
- Non-arteritic ischemic optic neuropathy (NAION) — sudden vision loss
- Sudden decrease/loss of hearing
- Avoid with other PDE5 inhibitors
- Prolonged erection/priapism — seek care if erection >4 h
Adverse reactions
- Headache
- Myalgia
- Nasopharyngitis
- Flushing
- Nausea
- Back pain
- Dyspepsia
- Nasal congestion
- Pain in extremity
Pregnancy Limited human data have not identified drug-associated risk; no adverse animal developmental effects at 7× MRHD
Lactation No human data; present in rat milk at ~2.4× plasma
NO BOXED WARNINGS
Principal riskFatal hypotension with nitrates, for up to 48 hours
Cost, est. cash$10–$500/month
Generic entry2018
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.
Mechanism of action: Tadalafil ballicule
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Memory aids: mascots and interaction avatars
