Patient’s Guide for Self Injection


For many years, doctors have been using various medications to improve circulation through blood vessels. These medications include papaverine, phentolamine and prostaglandin E 1(PGE1) etc. It has been found that these drugs can induce penile erection when injected directly into the penis. After detailed examination, the doctors have determined that I have a good response to prostaglandin E 1 or a combination of papaverine, phentolamine and prostaglandin E 1 injection and, if I wish, these drugs can be used to treat my impotence problem. This treatment has gained world­wide acceptance since 1983. Prostaglandin El was approved for penile injection by the FDA in 1995.


  1. Keep medication in the refrigerator between uses, especially if it has prostaglandin E1 (Caverject, Edex, Trimix). If you are travelling, keep the medication in an ice chest.
  2. Tear open an alcohol swab and wipe the rubber top of the bottle to sterilize it.
  3. Peel open the syringe carefully. Remove the protective cover from the needle. It is important that the needle not be contaminated by touching anything but the rubber bottle cap. Push the needle through the rubber stopper, then reverse the ampule so that it is upside down and pull on the plunger until 1.0 cc of the medication is withdrawn. Still holding the ampule upside down, inject whatever air remains in the syringe into the ampule and again withdraw fluid until there are no more air bubbles in the syringe and there is now the correct # of cc of the medication in the syringe. Pull the needle out of the ampule and lay the syringe on the edge of a flat surface with the needle projecting beyond the edge so that it touches nothing.
  4. Dosage: Your dose will be decided by your provider. Never increase the dose by more than a small amount (0.05cc) or else you run the risk of persistent, painful erection that may require a trip to the Emergency Room.
  5. Frequency of injection: not more than three times a week. Never more then once a day.
  6. The places for injection are limited by the anatomy of the penis and you must adhere to these. Changing injection sites from left to right as well as up and down shaft and back again is recommended.
  7. Grasp the head of the penis between the index finger and thumb. Gently pull the penis away from the body until the skin taut. When choosing an injection site, avoid any area where a vein is clearly visible. Wipe the skin with the alcohol swab. Pick up the syringe with the other hand pretty much as if throwing a dart and touch the point of the needle to the place chosen for the injection with light pressure.
  8. Hold the syringe at right angles to the skin, push lightly to penetrate the skin. (As there are few nerve endings for pain in this area, there will probably be minimal or no discomfort).
  9. Once through the skin (some resistance will be felt), push firmly forward until a distinct “give” is felt; the needle should now be in the right place (within the erectile bodies).  The whole length of the needle should be in up to the hub.
  10. Now, hold the syringe between the index and middle fingers and place a thumb on the plunger.  Inject the entire contents of the syringe slowly.  Then withdraw the needle from the penis.  Immediately apply pressure to the penis with the thumb and index finger for 2-3 minutes using the alcohol swab until there is no bleeding.
  11. Place the needle in the disposal box.
  12. If you contaminate the needle by touching it to any object other than the alcohol-wiped ampule stopper or penile skin, you must discard the syringe and start over. Do NOT insert a contaminated needle into the ampule.
  13. Tumescence of the penis and sometimes erection will occur within 5-15 minutes.  Many patients will not achieve an erection until sexual foreplay is started.  Some patients have noted decrease of penile sensation and difficulty ejaculating.  This is usually part of the impotence condition for which the injection is given, although it may be due to inadequate foreplay and excitement.


Bleeding from the injection site:

This usually results in a black and blue patch on the skin and usually disappears in a few days.  This is due to insufficient post injection pressure to the injection site or from puncturing one of the skin veins.  This can usually be prevented by applying pressure at the injection site for 1-2 minutes.  It is very important that the injection be carried out without undue haste and in good light.  You should wear glasses if needed.  If you have failed to penetrate the erectile tissues after injection, you will feel a burning sensation which will go away in about an hour and no erection will results.  In order to know that you are in the correct location, you should insert at a right-angle to the skin, feel the “give”, and the needle should be in the shaft of the penis up to the hub.

Prolonged erection (Priapism):

This is an easily managed but potentially serious complication.  If ignored, it may result in severe pain and may require a small operation.  In addition, it may make you completely impotent (i.e. cannot respond to even injections).  Therefore, only make SMALL adjustments in your dose, if needed.  IF you develop a full erection that lasts more than 3 hours, CALL US AT ONCE at.  Treatment of the condition is fairly simple: we put a small needle in the penis, drain the blood and inject a small amount of adrenaline.  If this is done early, usually there is minimal or no damage.

 Transitory pain:

About 10% of patients develop pain or discomfort in the head of the penis shortly after injection. This usually subsides spontaneously after a few minutes. It is more commonly seen in patients with impotence secondary to nerve problems.

Temporary swelling of the skin of the penis:

This is due to improper placement of the needle

No response:

This may result from:

  • Wrong technique
  • Expired medication.
  • Inadequate dose.

Scarring or deformity (curvature) of the penis

Infection of the penis


  1. Keep medication in the refrigerator.
  2. Use sterile injection technique.
  3. Inject only those sites designated.
  4. Limit the frequency and dose of injections as ordered.
  5. Do not inject any substance other than that provided.
  6. Do not share needles or medications with other people.
  7. Call immediately if erection lasts more than 3 hours.
  8. Examination every 3-4 months.