Short answer: Per the Caverject label, the first doses are given in the prescriber's office, starting at 2.5 mcg injected into the penis (1.25 mcg for ED from nerve injury), then stepped up until an erection suitable for intercourse lasts no more than 1 hour. Doses above 60 mcg are not recommended. 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 Caverject is approved for: Caverject is approved to treat erectile dysfunction, and as an add-on to other tests in diagnosing erectile dysfunction (sections 1.1 and 1.2). It is injected into the side of the penis (intracavernosal use).
Source
CAVERJECT (alprostadil) for injection, for intracavernosal use, prescribing information, Patient Information and Instructions for Use. Pharmacia & Upjohn (Pfizer). DailyMed, version published May 17, 2024. DailyMed setid a295fc1e-d82c-4f44-bc2d-a552bf594c98
Caverject is a powder in a 20 mcg or 40 mcg single-dose vial, mixed with 1 mL of bacteriostatic water to make 20 or 40 mcg/mL, and injected into the right or left side of the penis with a 29 or 30 gauge one-half inch needle, alternating sides each time (sections 2.3 and 2.4).
The first injections and dose finding are done in the prescriber's office, and the patient stays until the erection goes away. Home use starts after training in self-injection (sections 2.1 and 2.2).
An erection is expected within 5 to 20 minutes and should last no longer than 1 hour (section 17).
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 | If partial response | Further steps |
|---|---|---|---|
| Vascular, psychological or mixed cause | 2.5 mcg | Another 2.5 mcg within 1 hour | 5 to 10 mcg increments at least 24 hours apart |
| Purely nerve-related (for example spinal cord injury) | 1.25 mcg | Another 1.25 mcg within 1 hour | 5 mcg at least 24 hours later |
| Home maintenance | Dose found in the office | No more than 3 times weekly, at least 24 hours between doses |
| Dose | 20 mcg vial: volume to inject | 40 mcg vial: volume to inject |
|---|---|---|
| 1.25 mcg | 0.06 mL | --- |
| 2.5 mcg | 0.125 mL | --- |
| 5 mcg | 0.25 mL | 0.125 mL |
| 10 mcg | 0.5 mL | 0.25 mL |
| 15 mcg | 0.75 mL | 0.375 mL |
| 20 mcg | 1 mL | 0.5 mL |
| 25 mcg | --- | 0.625 mL |
| 30 mcg | --- | 0.75 mL |
| 40 mcg | --- | 1 mL |
The dose is titrated to the lowest effective dose; doses greater than 60 mcg are not recommended. Patients are re-evaluated regularly, every 3 months or as appropriate.
During titration, no more than 2 doses are given within 24 hours, and a new vial is used for each dose.
For diagnostic testing, a single dose that produces a rigid erection is used, following the vascular, psychological or mixed-cause regimen.
Mixed solution is used within 24 hours when kept at or below 77 F, and is not used if cloudy, colored or containing particles.
20 mcg vials are stored at 68 to 77 F. 40 mcg vials are refrigerated until dispensed, then kept at or below 77 F for up to 3 months or until expiration, whichever comes first.
The Caverject 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 Caverject 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.