Erectile dysfunction

Note: Drug treatments for erectile dysfunction

  • May only be prescribed on the NHS under certain circumstances and the prescription must be endorsed SLS; refer to the BNF for further details.
  • Most patients are not eligible under current NHS rules for NHS treatment. Where private prescriptions are issued, GPs may wish to advise patients that sildenafil is now very low cost and may be the preferable option.
  • Sildenafil and tadalafil are contra-indicated in patients receiving nitrates and nicorandil.
  • Use with caution in patients on alpha-blockers, eg doxazosin, tamsulosin.  
  • If prescribing after myocardial infarction/acute coronary syndrome, advise re-introduction at 1 month after cardiac event if patient is pain-free and does not require nitrates or nicorandil.
  • Sildenafil has a duration of action of around 6 hours and its onset of effect may be delayed if taken with food. Tadalafil has a longer duration of action (up to 30 hours) and may be preferred for patients for whom this represents a significant advantage.  Its onset of action is unaffected by food.
  • Serum testosterone should be measured on an early morning sample to exclude hypogonadism.
  • Both tadalafil and sildenafil should be tried at their maximum doses on several occasions before referring the patient to Urology for consideration of other therapies, eg transurethral or intra-cavernosal alprostadil or vacuum devices.  Psychosexual counselling should also be considered.
  • Vacuum pumps are available and prescribable in primary care following assessment and recommendation at a urology clinic

For further information see erectile dysfunction guidance.

SILDENAFIL (First Line)

Important: Therapy notes


Risk minimisation materials

Important: Formulation and dosage details

Formulation:

Tablets 25mg, 50mg, 100mg

Dosage:

Initially 50mg (older people, 25mg) approximately 1 hour before sexual activity, subsequent doses adjusted according to response to 25 to 100mg as a single dose as needed; maximum 1 dose in 24 hours (maximum single dose 100mg).

Notes:

Note: Sildenafil for pulmonary hypertensionThe initiation, prescribing and supply is from the National Specialist Service for pulmonary arterial hypertension (Scottish Pulmonary Vascular Unit or similar specialists) only. 
For further information see NHS inform

TADALAFIL

Important: Therapy notes

Important: Formulation and dosage details

Formulation:

Tablets 2·5mg, 5mg. 

Dosage:

For daily dosing

Important: Formulation and dosage details

Formulation:

Tablets 10mg, 20mg

Dosage:

For on demand dosing.

Initially 10mg approximately 30 minutes to 12 hours before sexual activity, subsequent doses adjusted according to response to 20mg as a single dose; maximum 1 dose in 24 hours. 

ALPROSTADIL

Important: Therapy notes

Important: Formulation

Intracavernosal injection 5 micrograms, 10 micrograms, 20 micrograms, 40 micrograms (s)

Important: Formulation

Double chamber cartridge 10 micrograms, 20 micrograms (s)

DAPOXETINE

Important: Therapy notes

Important: Formulation and dosage details

Formulation:

Tablets 30mg, 60mg (specialist initiation only)

Dosage:

For premature ejaculation in men who meet all the following criteria: poor control over ejaculation, a history of premature ejaculation over the past 6 months, marked distress or interpersonal difficulty as a consequence of premature ejaculation, and an intravaginal ejaculatory latency time of less than two minutes.

Last reviewed: 04 March 2021