The retinoid, properly
This is the product people abandon and it is the one that works. The reason for abandonment is always the same: started nightly, skin peeled and stung for two weeks, stopped.
The correct approach is twice a week for two weeks, every other night for a month, then nightly if the skin tolerates it, with a pea-sized amount for the whole face applied to dry skin. Buffering with moisturiser underneath is legitimate and helps more people than it hinders.
Judge it at three months. Retinisation, which is the adjustment period of dryness and flaking, takes six to twelve weeks and looks like the product failing. It is the product working.
Prescription against over the counter
Tretinoin is prescription and is the most-studied molecule in dermatology. Retinaldehyde and retinol are weaker and gentler; they work, more slowly, and are the right starting point for sensitive skin.
The practitioner can prescribe, and will, when it is appropriate. She will also tell you that a well-tolerated over-the-counter retinoid used every night for two years beats a prescription one abandoned in week three, which is the actual comparison most people are choosing between.
What we will not sell you
Anything with growth factors from a source we cannot verify. Anything sold on a subscription. A full line because you came in for one thing. Or a fifth active on top of four that are working, which is how people give themselves a damaged barrier and then blame their skin.