Caverject (Prostaglandin E1): Instructions, Pros and Cons, Side Effects

ED Oral vs Injective Treatments

Injective ED treatment drugs were invented much earlier than oral ED treatment medications. Despite that fact oral drugs are considered to refer to the first stage of ED treatment and injective drugs – to be the second one. It means if the oral Ed treatment drugs turn to be ineffective the doctor should prescribe injective ED treatment.

Oral ED treatment drugs or PDE5 inhibitors appeared less than 20 years ago with the invention of the pioneer – Sildenafil, which is widely known as Viagra. Then came Cialis (Tadalafil) and Levitra (Vardenafil). All the medications have similar therapeutic action, side effects and contraindications. They differ mainly by the duration of action. In the table below we provide the comparative analysis of ED oral and injective treatment methods.

PDE5 Inhibitors Injective ED treatment drugs
Effectiveness Very high (up to 90%) High (70-85%)
Duration From 4-5 to 36 hours 1 hour
Price High (for the original products), affordable (for generics) Affordable
Side effects Rare, some of them disappearing in the course of treatment Very few
Contraindications Cardio-vascular diseases, gastrointestinal disorders, blood diseases, co-administration with nitrate-containing drugs, antibiotics, antifungal medications etc. No alcohol is allowed. Sickle-cell anemia, penis deformations and implants, excessive sensitivity to the ingredients
Special skills needed No need Patient needs to have special skills of making injections
Special notes Prescribed with care for patients with diabetes Not prescribed for patients with diabetes

Pros and Cons of Injective ED Drugs

The major benefit of injective ED drugs one can mention high effectiveness regarding most types of erectile dysfunction. The other advantages include comfortable application, low risk of priapism development, rare side effects and constitutional reactions as well as rare contraindications. At the same time the necessity of injections and pain in the place of injection together with the fear of injections some patients may feel speak for the disadvantages of intracavernous ED treatment.

My Canadian Pharmacy survey of ED injection drugs

As intracavernous injections have been practiced for about 40 years several medications were applied in order to obtain better results.

Papaverine was the first medication used for the intracavernous injections. It is characterized by the ability to directly relax plain muscles. Its effectiveness makes up 40-70%. However, while treating with Papaverine the patient risks to suffer from prolonged erection or priapism, arterial hypotension and cavernous body sclerosis.

In 1980-ies Phenoxybenzamine and Phentolamine were used for the ED treatment. Further investigations of both medications and analysis of their side effects led to the refusal to apply these substances as a monotherapy. They started to be used in combination with Papaverine until the time of prostaglandins and neurotransmitters began.

Prostaglandin E is the drug of the next generation which is characterized by quite high effectiveness of 70-80%. Prostaglandin E stimulates specific receptors connected with Gs proteins. These receptors stimulate adenylate cyclase responsible for the formation of cAMP. As a result plain muscles of the cavernous body are relaxed very efficiently.

Trimix is another effective medication containing Papaverine, Phentolamine and Prostaglandin. It is considered to be one of the most effective medications for intracavernous injections.

Alprostadil is an artificial analogue of Prostaglandin E which successfully combines high clinical effectiveness (more than 70%) and safety. Alprostadil is an active ingredient of Caverject, one of the most popular medications for intracavernous injections.

Caverject review

Caverject refers to the group of prostaglandin E medications. It is provided in the form of solution containing 10 and 20 mcg of Alprostadil (synthetic analogue of prostaglandin E) and is used for intracavernous injections during the treatment of erectile dysfunction of various etiology: neurogenic, vascular, psychogenic or mixed.

Caverject is not prescribed for patients who:

  • Suffer from diseases that may lead to priapism (sickle-cell anemia, myeloma, leucosis);
  • Have anatomic deformations of penis (angulation, cavernosal fibrosis, Peyronie’s disease);
  • Have penis implants;
  • Suffer from excessive sensitivity to any ingredient of the medication.

Caverject is not used in patients who are not recommended to have sexual activity either. Caverject’s effectiveness is not studied in patients under 18 years old.

The dosage of Caverject should be defined individually and only by the doctor. The initial dosage is usually less by half than the further standard one. It is defined depending upon the patient’s health state and the etiology of the erectile dysfunction. In case of neurogenic ED the initial dosage should not exceed 1.25 mcg of Alprostadil, in case of psychogenic, vascular and mixed ED – 2.5 mcg. After the first injection the dosage should be increased step-by-step in order to reach the optimal erection enough to conduct sexual intercourse within 1 hour. If the coitus lasts longer than 1 hour the dosage of Caverject should be decreased.

Doctors recommend that Caverject should be injected not more than 3 times a week and only 1 dosage per day. Erection usually occurs in 5-20 minutes after the injection.

Average supporting dosage of Alprostadil is 5-20 mcg. Dosages exceeding 60 mcg are not recommended.

Side effects of Caverject are divided into the local and constitutional reactions. All side effects are reported in rare cases.

Local reactions to Caverject include pain and burning pain in penis, prolonged erection within 4-6 hours (in 4% cases), fibrosis (3-4%) including angulation and Peyronie’s disease, hematoma in the place of injection (in 3% cases), ecchymoma (in 2% cases). Nearly all the local reactions are caused by the wrong injection technic rather than the action of Alprostadil.

Rare side effects that occur in less than in 1% cases involve priapism (however in most cases spontaneous relaxation of penis was reported), balanitis, hemorrhage, inflammation, itching and edema of penis in the place of injection, bleeding from urethra, heat feeling, fungal infection, numb feeling, irritation, hyperesthesia, phymosis, erythema, painful erection, ejaculation disorder.

Constitutional reactions involve high blood pressure, dizziness, headaches, pain in back, upper respiratory tract infection, flu-like syndrome, sinusitis, nasal stuffiness, cough, prostatitis, pain syndrome.

In less than 1% cases the following constitutional reactions are reported: pain in testicles, testicle edema, heat in testicles, testicle thickening, scrotum redness or edema, pain in scrotum, hematuria, urination disorder, faster urination, spermatocele, pain in pelvis, arterial hypotension, tachycardia, vasodilation, peripheral vascular abnormalities, supraventricular extrasystole, vasovagal reactions, hypersthesia, muscular weakness, hyperhidrosis, rash, skin itching, nausea, dry mouth, increased creatinin in serum, cramp in leg, and pupillary dilation.