Why AUC is higher in older volunteers
In a healthy-volunteer comparison, elderly men (≥65) had 34% higher Cmax and 52% higher AUC than men 18-45.
That is why the start moves down. It is not a claim that the tablet 'does nothing' after 65.
Fixed-dose efficacy trials still saw 5, 10, and 20 mg work in men under 45, from 45 to under 65, and at 65 and older.
Stimulation still required at 5 mg
A 5 mg tablet that 'did nothing' on the couch is not a failed geriatric trial. Arousal still has to happen.
Two clean attempts at 5 mg beat a one-line 'too weak' rating. Then the prescriber may step toward 10.
Link the 10 mg start scan
Younger adults without inhibitors still open on 10 mg.
Rhythm avoids do not relax at 5 mg. Keep the QT tag on the same printout.
Is 20 mg forbidden after 65?
No. The labelled ceiling remains 20 mg once daily if a clinician steps up after effect and side effects.
Forum praise for 20 mg is not a first geriatric swallow. Open at 5 unless the prescriber wrote otherwise.
Hepatic 5 mg is a different reason
Child-Pugh B also starts at 5 mg, with a 10 mg ceiling. That is liver exposure, not age.
Do not mix those two 5 mg stories. Liver lives on the hepatic scan.
What start does age 65 ask for?
A starting dose of 5 mg should be considered in patients 65 years of age and older. That is the geriatric row.
Ten milligrams is the 'most patients' line, not the senior default. See the 10 mg start if you are younger and uninhibited.