Alprostadil injection
- Drugs List
- Therapeutic Indications
- Dosage
- Administration
- Contraindications
- Precautions and Warnings
- Pregnancy and Lactation
- Side Effects
- Monograph
Presentation
Injection containing alprostadil
Drugs List
Therapeutic Indications
Uses
Adjunct to other diagnostic tests in the diagnosis of erectile dysfunction
Treatment of erectile dysfunction
Treatment of erectile dysfunction in adult males due to neurogenic, vasculogenic, psychogenic or mixed aetiology.
An adjunct to other diagnostic tests in the diagnosis of erectile dysfunction.
Dosage
The first dose should be administered under a physician's supervision and self administration may only be undertaken after proper training. The dose of alprostadil should be individualised for each patient by careful titration under supervision by a physician.
An erection should develop approximately 5 to 15 minutes after injection and should remain for about 1 hour.
Adults
The usual dose ranges, dose titration and maximum doses in product literature varies according to the brand. Some formulations permit precise dose adjustment, but others brands are formulated to permit incremental dose adjustment only.
The lowest effective dose should be used that provides the patient with an erection that is satisfactory for sexual intercourse. It is recommended that the dose administered produces an erection the duration of which does not exceed one hour; if the duration is longer, reduce the dose.
The frequency of injection should not exceed once daily administration and not more than three times a week.
A dose greater than 40 micrograms is not routinely justified and this is the maximum permitted licensed dose for some formulations. (Some formulations are licensed for doses not exceeding 60 micrograms.)
Doses exceeding 20 micrograms should be prescribed with particular caution in patients with cardiovascular risk factors.
The usual range is 5 to 20 micrograms.
Erectile dysfunction of vasculogenic, psychogenic, or mixed aetiology
The initial dose is 2.5 micrograms.
The second dose is 5 micrograms if there is a partial response to the first dose, or 7.5 micrograms if there is no response to the first dose.
Then administer subsequent dose increments in steps of 5 to 10 micrograms until an optimal dose is identified.
If no response to a given dose, the next dose may be given within 1 hour. If there is a response, there should be a one day interval before the next dose is given.
Erectile dysfunction of neurogenic origin (starting dose less than 2.5 micrograms )
The initial dose is 1.25 micrograms
The second dose is 2.5 micrograms, or adjusted towards 2.5 micrograms, if there is no response to the first dose.
The third dose is 5 micrograms if there is no response to the second dose.
Then subsequent increments in steps of 5 micrograms until an optimal dose is identified.
If no response to a given dose, the next dose may be given within 1 hour. If there is a response, there should be a one day interval before the next dose is given.
Adjunct to diagnosis
Subjects without evidence of neurological dysfunction usually respond to a single 10 to 20 microgram dose of alprostadil injected into the corpus cavernosum and massaged through the penis. The majority of patients respond to a single 20 microgram dose.
Subjects with evidence of neurological dysfunction can be expected to respond to lower doses. An initial dose of 5 micrograms may be appropriate. The diagnostic testing dose must not exceed 10 micrograms.
Should an ensuing erection last for more than one hour detumescent therapy should be employed prior to the subject leaving the clinic. At the time of discharge from the clinic, the erection should have subsided entirely and the penis must be in a completely flaccid state.
Administration
For direct intracavernous injection.
A half inch, 27 to 30 gauge needle is recommended. Administration must be done under sterile conditions. Visible veins should be avoided.The site of injection is usually along the dorsolateral aspect of the proximal third of the penis. Both the side of the penis and the site of injection must be alternated.
Contraindications
Children under 18 years
Patients in whom sexual activity is inadvisable
Predisposition to priapism
Anatomical deformation of penis
Cavernosal fibrosis
Leukaemia
Multiple myeloma
Penile implant
Peyronie's disease
Severe cardiovascular disorder
Sickle cell disease
Sickle cell trait
Precautions and Warnings
Patients over 75 years
Risk factors for cardiovascular disorder
Coagulopathy
Congestive cardiac failure
Drug misuse
History of drug misuse
History of gastrointestinal disorder
History of transient ischaemic attack
Ischaemic heart disease
Psychiatric disorder
Pulmonary disease
Not for use with other agents for erectile dysfunction
Treat medical causes of erectile dysfunction before therapy
Some presentations may contain benzyl alcohol
For single use only
Treatment for priapism should not be delayed more than 6 hours
Monitor every 3 months especially in initial stages of self injection
Advise patient to report any erection lasting more than 4 hours
Advise patients to report lower gastrointestinal bleeding
Discontinue if cavernal fibrosis develops
Discontinue if penile angulation develops
Discontinue if Peyronie's disease develops
Male: Use of condoms is advised after completing injection
Advise patient on anticoagulant how to control bleeding at injection site
In patients unable to self inject, train partner to give injection
Patients should be carefully selected in terms of their suitability for self-injection therapy.
For patients who are unable to self-inject safely because of poor manual dexterity, poor visual acuity or morbid obesity, the partner should be trained in the injection technique and perform the injection.
The patient should be re-evaluated after the first injection and at regular (e.g. 3 monthly) intervals; noting any adverse reactions and reviewing the dose. If there is no erectile response during the titration phase, patients should be monitored for systemic adverse effects.
Prolonged erection and/or priapism may occur. Patients experiencing an erection lasting longer than 2 hours but less than 4 hours should contact the physician for dose re-evaluation. Patients should be instructed to report any erection lasting 4 hours or longer, to a physician immediately; treatment of priapism should not be delayed for more than 6 hours.
Painful erection is more likely to occur in patient's with anatomical deformations of the penis such as angulation, phimosis, cavernosal fibrosis, Peyronie's disease or plaques. Penile fibrosis, including angulation, Peyronie's disease or fibrotic nodules, may occur after intracavernosal injection of alprostadil and may increase with increased duration of use. Regular follow-up of patients including careful examination of the penis is strongly recommended.
In cases where alprostadil is used in higher frequencies that is recommended, there is an increased risk of penile scarring.
Patient with blood clotting disorders or taking concurrent anticoagulant therapy (such as heparin or warfarin) may have an increased risk of bleeding after intracavernosal injection. Relevant factors should be monitored and advise the patient to exert sufficient manual pressure on the injection site to minimise bleeding.
If bleeding at the site of injection occurs in a patient with a blood-borne disease, there is an increased risk of transmission of the disease to the partner. The routine use of a condom to reduce the risk of blood borne infection may be advisable. Intracavernosal injection of alprostadil does not prevent the transmission of sexually transmitted diseases.
Use with care in patients with coronary heart disease, congestive heart failure or pulmonary disease as sexual stimulation and intercourse can lead to pulmonary or cardiac events. Such patients should be examined and cleared for stress resistance by a cardiologist before treatment.
Pregnancy and Lactation
Pregnancy
Not indicated for use in women.
Small amounts of alprostadil may be added to the naturally occurring prostaglandin E1 (PGE1) in the semen. It is therefore recommended that adequate contraception is used if the patient's partner is of child-bearing potential. If the patients partner is pregnant, barrier methods of contraception should be used to avoid irritation of the vagina and guard against any risk to the foetus.
The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14 to 17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).
Lactation
Not indicated for use in women.
Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
Specialist advice is available from the UK Drugs in Lactation Advisory Service at https://www.midlandsmedicines.nhs.uk/content.asp?section=6&subsection=17&pageIdx=1
Counselling
Advise patient of the potential for breakage or bending of the needle if proper handling and injection techniques are not followed. Should the needle become bent the patient should not attempt to straighten it, they should remove the needle and attach a new, unused sterile needle to the syringe.
Advise patient to report to a physician any erection lasting 4 hours or more. The patient should be provided with an emergency contact number for his doctor or a clinic experienced in the management of erectile dysfunction.
The routine use of a condom to reduce the risk of blood borne infection may be advisable.
Advise patients to report lower gastrointestinal bleeding.
Side Effects
Abdominal pain
Abnormal ejaculation
Allergic skin reactions
Amnesia
Anaphylactic reaction
Anaphylactoid reaction
Asthenia
Balanitis
Buttock pain
Cerebrovascular accident
Difficulty in micturition
Dizziness
Dry mouth
Dysuria
Erythema
Fibrotic changes in corpora cavernosa
Fibrotic nodules
Gastro-intestinal haemorrhage
Genital pain
Haematoma
Haematuria
Haemosiderin deposits in the penis
Headache
Hypaesthesia
Hyperhidrosis
Hypersensitivity reactions
Hypertension
Hypotension
Increased pulse rate
Infections
Injection site reactions
Leg cramps
Lower limb pain
Muscle spasm
Mydriasis
Myocardial infarction
Myocardial ischaemia
Nausea
Numbness
Oedema
Pain during erection
Pelvic pain
Penile angulation
Penile deviations
Penile fibrosis
Penile infection
Penile irritation
Penile oedema
Penile pain
Penile warmth
Perineal pain
Peripheral vascular disorders
Peyronie's disease
Phimosis
Pollakiuria
Presyncope
Priapism (erection lasting 6 hours or longer)
Prolonged erection (lasting 4-6 hours)
Prostate abnormalities
Pruritus
Rash
Scrotal disorders
Scrotal oedema
Sensitivity
Serum creatinine increased
Spermatocele
Sweating
Syncope
Testicular disorders
Testicular mass
Testicular oedema
Testicular pain
Testicular swelling
Testicular thickening
Thrombocytopenia
Urethral bleeding
Urethral burning
Urethral stenosis
Urinary tract infections
Urinary urgency
Urticaria
Vasodilatation
Venous leak
Ventricular extrasystoles
Vertigo
Overdosage
It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.
The following number will direct the caller to the relevant local centre (0844) 892 0111
Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).
Further Information
Last Full Review Date: April 2017
Reference Sources
Joint Formulary Committee. British National Formulary. 72nd ed. London: BMJ Group and Pharmaceutical Press; 2016.
Summary of Product Characteristics: Caverject Dual Chamber 10 micrograms. Pfizer Limited. Revised December 2015.
Summary of Product Characteristics: Caverject Dual Chamber 20 micrograms. Pfizer Limited. Revised December 2015.
Summary of Product Characteristics: Caverject 10 micrograms powder for solution for injection. Pfizer Limited. Revised February 2017.
Summary of Product Characteristics: Caverject 20 micrograms powder for solution for injection. Pfizer Limited. Revised February 2017.
Summary of Product Characteristics: Caverject 40 micrograms powder for solution for injection. Pfizer Limited. Revised February 2017.
Summary of Product Characteristics: Viridal Duo 10 micrograms/ml Powder and Solvent for Solution for Injection. UCB Pharma Limited. Revised May 2019.
Summary of Product Characteristics: Viridal Duo 20 micrograms/ml Powder and Solvent for Solution for Injection. UCB Pharma Limited. Revised May 2019.
Summary of Product Characteristics: Viridal Duo 40 micrograms/ml Powder and Solvent for Solution for Injection. UCB Pharma Limited. Revised May 2019.
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