Goal of therapy:
(1) sufficient erection to permit intercourse
(2) complete detumescence in one hour
Dose ranges: 0.2 to 60 µg (doses higher than 60 µg are possible but are not recommended). Most patients require doses in the range of 5-20 µg.
Titration in patients with pure neurogenic ED (after spinal cord injury):
(1) Start at 1.25 µg.
(2) If there is no response, then increase the second dose to 2.5 µg.
(3) If there is no response to the second dose, then increase the third dose to 5.0 µg.
(4) Subsequent doses proceeding in increments of 5 µg. If there is no response to an given dose, the next higher dose can be given within 1 hour.
(5) If there is a response, then there should be at least 1 day before making the next injection.
Titration in patients with vasculogenic, psychogenic, mixed ED:
(1) Start at 2.5 µg.
(2) If there is no response, increase the second dose to 7.5 µg, with subsequent doses proceeding in increments of 5-10 µg. If there is no response to an given dose, the next higher dose can be given within 1 hour.
(3) If there is a partial response, increase the second dose to 5.0 µg, with subsequent doses proceeding in increments of 5-10 µg.
(4) If there is a response, then there should be at least 1 day before making the next injection.
where:
• The description of the dosing schedule is a little ambiguous if there is no response. My reading is that you can try 2 injections during 1 visit if there is no response. An alternative reading would be that you could keep giving an injection every hour until you got a response, but this would seem hazardous in practice.
• If a second dose is given in a person with no response, I would imagine it should be injected in the side opposite that used for the first injection.
Injections:
(1) Titration is done under medical supervision.
(2) Self-injection by the patient can be performed if the patient can demonstrate the appropriate skills.
(3) The skin should be cleansed with an alcohol swab before making the injection.
(4) Injections should alternate between the left and right corpus cavernosum.
(5) The drug should not be injected directly into a vein.
Maintenance dosing:
(1) If the duration of the erection is greater than 1 hour, then the subsequent doses should be reduced.
(2) Adjustment in dosage should be done only after consulting with a physician, especially if larger doses are required.
