Sexual Health · Oral
PDE5 Inhibitors
Sildenafil and tadalafil, the first-line, best-studied treatment for erectile dysfunction. Available as-needed or as a low daily dose.
Already know this is what you want? The second option books the appointment straight away. Not sure yet? See the labs first.
Your consult is free. We will not prescribe this, or anything, before a clinician has spoken with you. Final cost depends on the form and dose prescribed.

Mechanism
Blood flow, on demand.
PDE5 inhibitors relax the smooth muscle in penile blood vessels, allowing normal blood flow in response to arousal. They do not create arousal, they remove a mechanical barrier to it.
Sildenafil works in roughly 30–60 minutes and lasts around four to six hours. Tadalafil takes longer to peak but lasts up to 36, which is why some patients prefer a low daily dose and no clock-watching.
ED is frequently an early cardiovascular signal. Your evaluation screens for that rather than treating the symptom in isolation.

Protocol
How treatment usually runs.
A typical schedule. Yours is set by your clinician, and adjusted as you go.
| Phase | Weeks | Typical | Purpose |
|---|---|---|---|
| As-needed (sildenafil) | , | 25–100 mg, 30–60 min before | Duration roughly 4–6 hours. |
| As-needed (tadalafil) | , | 10–20 mg, 1–2 hours before | Duration up to 36 hours. |
| Daily (tadalafil) | , | 2.5–5 mg once daily | Removes timing entirely. |
What to expect
Honestly, over time.
Test run
Effectiveness is judged over several attempts, not one.
Dial in the dose
Your provider adjusts strength and timing based on response.
Settled routine
Many patients switch to low daily dosing at this point.
Root cause
Persistent ED warrants hormone and cardiovascular workup.
Evidence
What the research shows.
PDE5 inhibitors are effective for a large majority of men with erectile dysfunction and have decades of safety data behind them.
Response improves with correct dosing and repeated attempts, a single unsuccessful trial is not a treatment failure.
Results vary. Clinical trial results apply only to the FDA-approved branded medication specifically identified and do not apply to compounded medications. All medications must be prescribed by a licensed provider based on medical necessity.
Safety and eligibility
Your consult and labs screen for all of the following.
- Never combine with nitrates or nitric-oxide donors, the interaction can cause a dangerous drop in blood pressure.
- Tell your provider about heart disease, recent stroke, low blood pressure, or alpha-blocker use.
- Common side effects include headache, flushing, nasal congestion and indigestion.
- Seek emergency care for an erection lasting more than four hours, or sudden vision or hearing loss.
FAQ
PDE5 Inhibitors questions.
Typically 30 to 60 minutes, with effects lasting around four to six hours. A heavy or high-fat meal can delay onset. Tadalafil takes one to two hours but lasts up to 36.
Neither is universally better. Sildenafil is shorter-acting and taken as needed; tadalafil lasts far longer and can be taken as a low daily dose that removes timing from the equation. Preference and side-effect profile usually decide.
Often yes, but never with nitrates, and with caution alongside alpha-blockers. Your provider reviews your full medication list and cardiovascular history before prescribing.
It can. Erectile dysfunction is frequently an early marker of cardiovascular disease, low testosterone or diabetes. That is why your evaluation looks at the underlying cause rather than only the symptom.
We will not prescribe before we understand you.
Book a one-to-one consult with the clinical team. We talk through your goals, order the bloodwork that matters, and build a plan from what we find.


