Caverject Impulse Information Pack - Web Version

Source: Pfizer Caverject Impulse Information Pack (alprostadil / prostaglandin E1, Pfizer Australia). The PDF copy is available here: Download the PDF (Caverject Impulse Information Pack). Content reproduced for accessibility. The full overview of penile injection therapy at Urology NSW is on the intracavernosal injection therapy page.

About this medication

Caverject Impulse is a single-use device that delivers a small dose of alprostadil (also called prostaglandin E1) by injection into the side of the penis. It is one of the recognised treatment options for erectile dysfunction (ED).¹

It is a prescription-only medication. The first dose is given in the clinic so that response and dose can be assessed, and patients are then trained one-on-one by the men's health pharmacist before self-administering at home. A general overview of injection therapy at Urology NSW (who it suits, what to expect, and how it fits with other ED treatments) is on the intracavernosal injection therapy page.

Caverject Impulse is supplied in two strengths in Australia: 10 micrograms and 20 micrograms per device. Your prescribed dose will be written on your prescription and confirmed in your training session.

Before you use Caverject Impulse

• Wash and dry your hands before using Caverject Impulse. If your partner wishes to be involved in preparing or giving the injection, they should also wash and dry their hands.
• Caverject Impulse is a single-use device which can administer only one dose.
• It is important that you follow the instructions carefully to prepare and inject Caverject Impulse.
• It is important that you also read the Pfizer Consumer Medicine Information (CMI) leaflet available from your pharmacist or at www.pfizer.com.au, and follow your doctor's advice.

Storage

You can prepare and store your Caverject Impulse for up to 24 hours before using it. The prepared device must be stored in the refrigerator at 2 to 8 degrees Celsius. Do not freeze.

Penile anatomy in plain terms

The injection is given into the side of the shaft of the penis, into the spongy erectile tissue called the corpus cavernosum. There are two corpora cavernosa side by side; either side may be used and the side is rotated each time to reduce scarring. The urethra (the urine and semen tube) runs along the underside of the penis and is deliberately avoided. The fine needle supplied with the device is short enough that, used correctly on the side shaft, it does not reach either the urethra or the central nerves and arteries on the top of the penis.

The full anatomy diagrams in the printed pack (sagittal view of the male pelvis, and a cross-section of the penis showing the corpora cavernosa, corpus spongiosum and tunica) are clearer in the printed brochure than they are in text. If you do not have a printed copy, please ask in the rooms or download the PDF above.

How to prepare your dose - device preparation steps 1 to 5

The Pfizer pack walks through the steps of getting the device ready, as below. Each step in the printed pack is illustrated with a photograph of the corresponding action; please refer to the printed pack or the PDF above for the visual guide.

Step 1 - Connect the needle to the device

• Remove the device and the capped needle from the box.
• Clean the grey rubber membrane at the tip of the device with one of the alcohol swabs provided.
• Completely peel the foil from the needle cap.
• Hold the syringe with the needle-end pointing upwards.
• Attach the needle onto the tip of the device by pushing and turning until it is firmly in place.

Step 2 - Remove the outer needle cap

• Pull off the outer cap from the needle.
• Hold the syringe with the needle-end pointing upwards.
• The plunger rod will be in the extended position.

Step 3 - Mix the powder and the liquid in the device

• Hold the device with the needle-end pointing upwards, gripping the blue chamber with one hand.
• Turn the plunger rod as shown in the printed pack until it will not turn any further (fully wound).
• The reconstituted solution will now appear in the clear chamber.
• The solution may appear cloudy at first. Gently shake to make sure the solution is evenly mixed and the powder has dissolved.
• Do not use the device if the solution remains cloudy or contains particles.

Step 4 - Remove the inner needle cap

• Hold the device with the needle pointing upwards.
• Carefully remove the inner cap from the needle.
• Do not touch the tip of the exposed needle.
• The needle is very fine. Take care not to bump it.
• Do NOT use the device if the needle is bent.

Step 5 - Remove air from the device

A few drops will appear at the needle tip during this step. This is expected.

• Remove any large bubbles by gently tapping the clear chamber with your finger.
• Ensure the plunger rod is still fully wound.
• Hold the device in one hand as shown in the printed pack, with the needle-end pointing upwards.
• Remove the air from the clear chamber by pressing the plunger rod with the thumb as far as it will go.
• If you need to use both hands to complete this step, the plunger rod must be pushed directly upwards - do not twist.

Pfizer instruction video

Pfizer also provides a short instruction video on how to prepare and inject Caverject Impulse. It is available through the Pfizer Meds app on the Apple App Store and Google Play. You can also scan or enter the barcode on your Caverject Impulse pack to access information on the medicine, including the instruction video.

Risks and safety information

As with any medical treatment, Caverject Impulse has potential side effects. The most important to be aware of are:

• Penile pain or aching at the injection site or during the erection. This is the most common side effect of alprostadil and is more common with some doses than others.
• Bruising or small bleeding at the injection site (haematoma or ecchymosis), particularly in the first few weeks while technique is being established.
• Prolonged erection or priapism - an erection lasting more than four hours. Priapism is uncommon but is a medical emergency: you must seek urgent medical attention if an erection has not resolved within four hours of an injection. Untreated priapism can cause permanent damage to the erectile tissue.^{1, 2}
• Penile fibrosis or scarring with longer-term use, including a risk of penile deformation. This is one of the reasons careful technique, correct dose, and rotation of the injection site matter, and why follow-up review is important.
• Other reported effects include haemorrhage, inflammation, swelling, itching or oedema at the injection site.

Caverject Impulse is not suitable for everyone. It should not be used by men with conditions that predispose to priapism (for example, sickle cell disease, multiple myeloma, or leukaemia), in men with anatomical deformation of the penis, in men with penile implants, in men where sexual activity is inadvisable or contraindicated, or in newborns, women or children. Patients on anticoagulants may have a higher risk of bleeding at the injection site. The full prescribing information is in the Pfizer Product Information for Caverject Impulse, available at www.pfizer.com.au.

Your specialist will assess these factors before the first injection. If anything changes (a new diagnosis, a new medication, a new bleeding tendency), let the rooms know before your next dose.

Pfizer contact and prescribing information

For additional information about Caverject Impulse, Pfizer Australia provides the following points of contact (printed on the back cover of the pack):

• Telephone: 1800 675 229
• Fax: 1800 675 295
• Email: medicalaffairs.anz@pfizer.com
• Web: www.pfizer.com.au

Caverject Impulse 10 micrograms and 20 micrograms powder for injection are not listed on the Pharmaceutical Benefits Scheme (PBS). For Repatriation Pharmaceutical Benefits Scheme (RPBS) information, refer to the PBS schedule.

What to do next

• Read the full overview of intracavernosal injection therapy at Urology NSW.
• Read the short version on penile injection therapy.
• Learn about the in-house men's health pharmacist service that delivers the training appointment.
• Read the broader erectile dysfunction page to see how injection therapy fits with the other treatment options.
• Contact Urology NSW or call 02 8382 6980 to make or change an appointment.