1 What is Caverject?

Brand: Caverject, Edex

Generic: Alprostadil

Alprostadil injection is used to treat men who have erectile dysfunction (sexual impotence). It belongs to a group of medications called vasodilators that increase blood flow by expanding blood vessels. This medication causes an erection because it increases the blood flow to the penis.

Alprostadil should not be used as a sexual aid by men who do not have erectile dysfunction. If the medication is not used properly, permanent damage to the penis and loss of ability to have erections may result.

This medication is used alone or with medical tests to help diagnose erectile dysfunction that may be caused by nerve or blood vessel problems in the penis.

This medication is only available with your doctor’s prescription.

This medication is available in the following forms:

  • Powder for Solution
  • Kit
  • Solution
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2 What to know before using

As with all medicines, the risks must be compared to how much a medication will help you. This is a decision that you and your doctor will make together. For this medication, there are many things that need to be considered:


Inform your doctor if you have ever had an allergic reaction to any other medications. It is also important to inform your doctor of any non-medicine allergies such as foods, dyes, preservatives or animals.


This medication is not for use in children.


No appropriate studies have been performed on the relationship of age to the effects of this medication in the elderly. However, geriatric patients are more likely to have age-related kidney problems, which may require caution and an adjustment in dose.


This medication is listed as Pregnancy Category C. This means that animal studies have shown an adverse effect and no studies have been performed on pregnant women OR there are no adequate studies on pregnant animals and pregnant women.


There are no up-to-date studies in women for determining infant risk when using this medication while breastfeeding. Weigh the potential risks with the benefits before taking this medication while breastfeeding.

Drug Interactions

Certain medications should not be used together. However, in certain cases, two medications may be used together, even if an interaction might occur. In these cases, your doctor may want to change your dose
or take other precautions. When taking this medication, it is important that you inform your doctor if you are taking any of the medications listed below. The following interactions were selected on the basis of potential significance and are not all-inclusive.

Using this medication with any of the following is not recommended. Your doctor may decide not to treat you with this medication, or change some of the other medications you take:

Other Interactions

Certain medications should not be used while eating, or while eating certain foods in case of negative interactions. Using alcohol or tobacco with certain mediations may also cause negative interactions. Talk with your doctor about the use of your medication with food, alcohol or tobacco.

Other Medical Problems

Pre-existing medical problems may affect the use of this medication.

Be sure to tell your doctor if you have any other medical problems, especially:

  • Abnormal penis, including curved penis and birth defects of the penis
  • Heart or blood vessel disease
  • Leukemia (blood related cancer)
  • Multiple myeloma (blood related cancer)
  • Priapism (prolonged erection)
  • Sickle cell anemia (blood disorder)
  • Sickle cell trait - Chance of problems occurring may be increased and this medicine should be used with caution in these patients.
  • Bleeding problems - Chance of bleeding at the injection site may be increased.
  • Kidney disease - Use with caution. The effects may be increased because of slower removal of the medicine from the body.
  • Priapism, history of - Patients with these conditions have an increased risk of priapism (erection lasting longer than 6 hours) while using alprostadil.

3 Proper usage

This medication is given as a shot into your penis. You will receive the first dose in your doctor’s office to figure out the best dose for you. You will need to stay in the office until your erection is gone.

This medication comes with a patient information brochure. It is very important that your read this information. Ask your doctor if you have any questions.

There are several alprostadil products that can be injected. Even though the injection method of mixing is different. Be sure you know which product you will be using and the proper way to mix it.

Alprostadil for Injection (Caverject, Edex) is available as a powder. Caverject must be mixed with a solution called Bacteriostatis Water for Injection USP. Edex must be mixed with a solution called Sodium Chloride Injection USP. The solution for mixed comes with your product and may already be loaded into a syringe or in a vial.

It is important to follow several steps to prepare your injection correctly. Before drawing up the medication into the syringe:

  • Wash your hands with soap and water.
  • Set the bottles on a clean, flat surface. Wipe the top of the injection bottles with an alcohol swab. Do not wipe the needle.
  • You many need to attach the needle to the syringe. Do not take the cap off yet.

How to mix Caverject:

If the syringe already contains Bacteriostatic Water for Injection USP, then you only need to add the plunger to the syringe:

  • Pick up the rod-like plunger and place it within the barrel of the syringe until it touches the rubber piece. Gently screw the plunger into the rubber piece until it seems secure. Do not use a lot of force.
  • Hold the syringe by the barrel and take the cap off the needle.
  • You are now ready to mix the water and powder. Skip to the directions “To mix the water and powder”

If the syringe does not already contain Bacteriostatic Water for Injection USP, you must withdraw 1mL of the solution from the provided bottle:

  • Take the cap off the needle. Pull the plunger back to the 1mL mark on the syringe. This pulls air into the syringe. Insert the needle into the rubber top of the bottle while it is upright and inject the 1mL of air into the bottle.
  • Turn the bottle upside down using one hand. Be sure the needle tip is covered by solution.
  • Pull the plunger back slowly to withdraw 1mL of solution into the syringe. Remove the needle and skip to the directions “To mix the water and powder.

To mix the water and powder:

  • Insert the needle into the bottle of alprostadil and inject 1mL of Bacteriostatic Water for Injection USP from your syringe into the bottle of alprostadil.
  • Remove the needle from the bottle.
  • Gently swirl the bottle to mix the powder into the solution, turning it upside down to wet all the powder in the bottle.
  • Follow the directions “How to draw your dose into the syringe”.

How to mix Edex

The syringe already contains Sodium Chloride Injection USP. You only need to attach the needle to the syringe and add the plunger.

  • Remove the needle from the package, but do not remove the needle cap. Gently screw the needle into place at the syringe tip.
  • Pick up the plunger and place it in the barrel of the syringe until it touches the rubber piece. Gently screw the plunger into the rubber piece until it seems secure. Do not use a lot of force.
  • Hold the syringe by the barrel and take the cap off the needle.
  • Inset the needle into the bottle of alprostadil and inject 1.2mL of Sodium Chloride Injection USP into the powder.
  • Remove the needle from the bottle, holding the barrel of the syringe.
  • Gently swirl the bottle to mix the powder into the solution, turning it upside down to wet all the powder in the bottle.
  • Use the mixture within 24 hours of mixing it.
  • Follow the directions “How to draw your dose into the syringe”.

How to draw your dose into the syringe (Caverject, Edex):

  • Make sure the solution is clear. Do not use the mixture if you see anything solid, or if the solution is cloudy or coloured.
  • After the solution is mixed and the needle inserted into the bottle, turn the bottle upside down. Be sure the needle tip is covered by solution. Pull the plunger back slowly to draw the correct dose of medication into the syringe.
  • Hold the syringe with the measuring scale at eye level to see that the proper dose is withdrawn and to check for air bubbles. To remove air bubbles, gently tap on the barrel of the syringe to move any bubbles to the top of the syringe near the surface.
  • If your dose is too low, withdraw more solution from the bottle. If it is too much, put some back in the bottle.

How to give the injection

  • Choose a spot on your penis as directed by your doctor.
  • Clean the injection site with alcohol. Sitting upright or slightly reclined, hold your penis against the side of your thigh so that it cannot move.
  • Remove the cover of the needle and hold the needle at a 90-degree angle to the place of injection.
  • Insert the needle until almost all of the metal part of the needle is inserted into the penis.
  • Do not inject the medication just under the surface of the sin, at the top or head of the penis or at the base of the penis near the scrotum or testes. Avoid injecting the medication into blood vessels that you can see.
  • Press the plunger down slowly, taking 5-10 seconds to release the dose.
  • The injection is not normally painful. If it injection is very painful or you notice bruising or swelling at the injection site, that means you are injecting the medication under the skin. Stop, withdraw the needle and reposition it properly before continuing with the injection.
  • Remove the needle and recap it.
  • After you have completed the injection, put pressure on the place of injection for 5 minutes or until any bleeding stops. This will prevent bruising. Massage your penis as instructed by your doctor. This helps the medication to spread to all parts of the penis so that the medication works better.

Choose a different injection site each time you use this medication. This will help prevent skin issues. This includes switching the place of injection from the right side for one injection to the left side for the next injection.

After a single-use injection is mixed, the medication must be used immediately. Throw away any unused mixture in the syringe, as it cannot be stored for a later injection.

Do not reuse or share needles or cartridges.

Dispose of your materials properly. Caverject comes in a plastic case that can be permanently locked with the red locking device included with the packaging. When the case label is removed, you can see a hole in the centre of the case. The red locking device can be inserted and, by firmly pressing down with your thumb, you will permanently lock the case. This makes it safe to be thrown away.

This medication normally begins to work in 5-10 minutes. You should attempt intercourse within 10-30 minutes after using the medication. An erection may continue after ejaculation.


Different patients will be given a different dose of this medication based on the strength of the medication. The number of doses you take each day, the time between doses and the length of time you take this medication depends on the reason you are taking this medication. The following information only includes the average dose of this medication. If your dose is different, do not change it without first speaking to your doctor.

  • Adults - 1.25-60mcg as a single dose once a day. Your exact dose will be determined by your doctor. Inject this medication very slowly into your penis as shown by your doctor 10-30 minutes before intercourse. Allow 5-10 seconds to completely inject the dose. Do not inject more than one dose within 24 hours. Do not use this medication for more than 2 days in a row or more than 3 times per week.


Store in the refrigerator. Do not freeze.

This medication, while in powder form, can be stored at room temperature between 15-25C/59-77F for 3 months. After it is mixed, the solution must be used immediately.

Keep our of the reach of children.

Do not keep expired medication or medication you no longer need. Ask your doctor how to dispose of any medication you do not use.

4 Precautions to take

Do not use this medication if you have a penile implant unless advised by a doctor.

If you use too much of this medication, the erection lasts to long and does not reverse when it should. This condition is called priapism. If the erection is not reversed, the blood supply to the penis may be cut off and cause permanent damage.

Contact your doctor immediately if the erection lasts longer than 4 hours or if it becomes painful. This may be a sign of priapism and must be treated immediately.

If you notice bleeding at the injection site, put pressure on the area until the bleeding stops. If it doesn’t stop within 10 minutes, inform your doctor.

5 Potential side effects

A medication may produce unwanted affects along with the intended effects. Although not all of these side-effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if you experience any of the following side-effects:


  • Curving of the penis with pain during erection
  • Erection continuing for 4-6 hours
  • Erection continuing longer than 6 hours with severe and continuing pain
  • Swelling or pain of the testes

Some side effects that may occur do not normally need medical attention. These may leave as your body becomes accustomed to treatment. Ask your doctor about ways to prevent or reduce some of these side effects.

Talk to your doctor if any of the following side effects continue or are bothersome, or if you have questions:

More common:

  • Short-term bleeding and pain at injection site
  • Painful erection


  • Bruising or clotted blood at injection site, normally caused by incorrect injection

Some patients may experience other side effects that are not listed. Check with your doctor if you notice any other side effects.

Ask your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

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