Caverject Impulse

What it is

Caverject Impulse contains alprostadil. It is available as a dual chamber syringe in two strengths, 10 and 20 micrograms, with each 0.5 mL cartridge delivering a maximum dose of 10 or 20 micrograms of alprostadil. Caverject Impulse is a powder for intracavernosal injection. It is administered by direct intracavernosal injection.

Approved indications

— Treatment of erectile dysfunction in adult males. — May be a useful adjunct to other diagnostic tests in the diagnosis of erectile dysfunction.

Dosing overview

Before initiation of treatment, patients should be carefully assessed by a specialist practitioner in erectile dysfunction with appropriate training in the use of this medicine, and the dose should be titrated carefully according to individual need. For erectile dysfunction of neurogenic or psychogenic aetiology, the generally recommended initial dose is 2.5 micrograms with subsequent upward titration in increments of 2.5 micrograms. For erectile dysfunction of arteriogenic origin or due to other organic causes, the generally recommended initial dose is 5 micrograms with subsequent upward titration in increments of 5 micrograms. When the aetiology is unknown or Caverject Impulse is being used as an adjunct in diagnosis, the generally recommended initial dose is 2.5 micrograms with subsequent upward titration in increments of 2.5 micrograms. The majority of patients obtain a satisfactory response with doses in the range of 10–20 micrograms. The maximum recommended frequency of injection is no more than once in a 24 hour period and no more than three times weekly.

Key safety warnings

Prolonged erection and/or priapism are known to occur following intracavernosal administration of vasoactive substances, including alprostadil. The treatment of priapism may include aspiration, intracavernosal injection of sympathomimetic amines or surgery. In evaluating a patient for alprostadil therapy, the physician should determine which interventions would be appropriate for the individual patient. Patients should be instructed to report to a physician any erection lasting for an overly prolonged time period, such as 4 hours or longer. Penile fibrosis, such as angulation, phimosis, cavernosal fibrosis, fibrotic nodules and Peyronie's disease or plaques, may occur following intracavernosal administration of Caverject Impulse, and the occurrence of fibrosis may increase with increased duration of use. At regular visits the physician must examine the penis carefully, preferably in the erect state, for potential development of fibrotic changes. If there are signs of fibrotic complications, treatment must be stopped immediately. Patients on anticoagulants such as warfarin or heparin may have an increased propensity for bleeding after the intracavernosal injection. Caverject Impulse can induce a small amount of bleeding at the site of injection, and in patients infected with blood-borne diseases, this could increase the transmission of such diseases to the partner. Caverject Impulse uses a superfine needle for administration. As with all superfine needles, the possibility of needle breakage exists. Needle breakage, with a portion of the needle remaining in the penis, has been reported and in some cases required hospitalisation and surgical removal.

Contraindications

Caverject Impulse should not be used in patients who have a known hypersensitivity to alprostadil or any of the excipients, or in patients who have conditions that might predispose them to priapism such as sickle cell anaemia, multiple myeloma or leukaemia. Patients with pre-existing penile fibrosis should not be accepted into intracavernosal self-injection therapy. Caverject Impulse should not be used in patients with anatomical deformation of the penis, such as angulation, cavernosal fibrosis or Peyronie's disease. Caverject Impulse should not be used in men for whom sexual activity is inadvisable or contraindicated. Caverject Impulse should not be used in women. It should not be used in children and is not for use in newborns. Caverject Impulse should not be used in patients with penile implants.

PBS listing

Caverject Impulse 10 micrograms intracavernosal injection with diluent in single use syringe is listed on the PBS with authority required restriction at an ex-manufacturer price of A$33.13. The 20 micrograms strength is also listed with authority required restriction at an ex-manufacturer price of A$42.67.

Regulatory history

Caverject Impulse was first approved on 29 July 2002. Both the 10 microgram and 20 microgram strengths were listed on the Australian Register of Therapeutic Goods on 29 July 2002 in licence category RE.