Short answer: The Edex label gives a dose range of 1 to 40 mcg injected into the penis over 5 to 10 seconds. Titration starts in the doctor's office at 2.5 mcg (1.25 mcg for spinal cord injury) and steps up until an erection suitable for intercourse lasts no more than 1 hour. At home, it is used no more than 3 times a week, at least 24 hours apart.
This is what the FDA label says. Follow your prescriber. Your prescriber may use a different dose or pace than the label's standard schedule.
What Edex is approved for: Edex is approved to treat erectile dysfunction caused by nerve, blood vessel, psychological or mixed causes (Indications and Usage). It is injected into the side of the penis (intracavernous use).
Source
EDEX (alprostadil for injection), prescribing information and patient information. Endo USA. DailyMed, version published July 13, 2026. DailyMed setid e8b8ec8d-1318-43e4-a182-446e9f9579de
Edex comes in single-dose, dual-chamber cartridges used with a reusable injection device. Pushing the plunger mixes 1.075 mL of saline into the powder, giving 10, 20 or 40 mcg per mL (Preparation of Solution and How Supplied).
The solution is prepared right before use and used immediately; leftover solution is thrown away. It is injected over 5 to 10 seconds, usually along the side of the base third of the penis, alternating sides and avoiding visible veins (Dosage and Administration).
The first injections are done in the doctor's office, and home use starts only after training in self-injection (At-Home Dosing Instructions).
The table below is the label's schedule, from the Dosage and Administration section. Numbers are copied exactly; the section is in brackets.
| Type of ED | Starting dose | How it steps up |
|---|---|---|
| Vascular, psychological or mixed cause | 2.5 mcg | Partial response: +2.5 mcg to 5 mcg, then 5 to 10 mcg steps. No response: second dose may be 7.5 mcg, then 5 to 10 mcg steps |
| Purely nerve-related (spinal cord injury) | 1.25 mcg | +1.25 mcg to 2.5 mcg, +2.5 mcg to 5 mcg, then 5 mcg steps |
| Both | In the office | No response: next higher dose may be given within 1 hour. Response: at least 1 day before the next dose |
| Home maintenance | Dose found in the office | No more than 3 times weekly, at least 24 hours between doses |
The dose range is 1 to 40 mcg; doses greater than 40 mcg have not been studied. Mean doses at the end of titration were 10.7 mcg (1 to 20 mcg study) and 21.9 mcg (two 1 to 40 mcg studies).
The target is an erection suitable for intercourse lasting no longer than 1 hour; if it lasts longer, the dose is reduced. The lowest effective dose is used.
During home use, a visit every 3 months is recommended to check effect and safety and adjust the dose if needed.
Older patients needed higher minimum effective doses on average but follow the same titration as younger patients.
Stored at 77 F, with excursions allowed between 59 and 86 F.
The Edex label gives no missed-dose rule. It is used as needed before sexual activity, no more than 3 times a week with at least 24 hours between doses.
In Dose Track you set up Edex as a protocol with the dose and schedule your prescriber gave you. A protocol can hold dose steps, each with its own dose and length in days or weeks, so a step-up plan like the one on the label can be entered once and the app moves to the next step on its own. Reminders follow the schedule, and every dose is logged with the date and time, so you can see which step you are on and when your last dose was. The app follows what you enter; it does not choose or change a dose.
This page is what the FDA label says, in plain words. It is not medical advice. Follow your prescriber, and ask them or your pharmacist about anything here.