Pulmonary arterial hypertension (initiated under
specialist supervision)
▶BY MOUTH
▶Adult: 20 mg 3 times a day
▶BY INTRAVENOUS INJECTION
▶Adult: 10 mg 3 times a day, use intravenous route when
the oral route is not appropriate
Erectile dysfunction
▶BY MOUTH
▶Adult: Initially 50 mg, to be taken approximately 1 hour
before sexual activity, adjusted according to response
to 25–100 mg (max. per dose 100 mg) as required, to be
taken as a single dose; maximum 1 dose per day
Digital ulcers [associated with systemic sclerosis]
▶BY MOUTH
▶Adult: 25 mg 3 times a day, increased to 50 mg 3 times
a day
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DUE TO INTERACTIONS
▶When used for Erectile dysfunction Manufacturer advises a
starting dose of 25 mg with concurrent use of moderate
and potent inhibitors of CYP3A4. Manufacturer advises if
concurrent use of ritonavir is unavoidable, the max. dose
should not exceed 25 mg within 48 hours.
▶With oral use for Pulmonary arterial hypertension
Manufacturer advises reduce dose to 20 mg twice daily
with concurrent use of moderate inhibitors of CYP3A4.
Manufacturer advises reduce dose to 20 mg once daily with
concurrent use of some potent inhibitors of CYP3A4 (avoid
with ketoconazole, itraconazole and ritonavir).
▶With intravenous use for Pulmonary arterial hypertension
Manufacturer advises reduce dose to 10 mg twice daily
with concurrent use of moderate inhibitors of CYP3A4.
Manufacturer advises reduce dose to 10 mg once daily with
concurrent use of some potent inhibitors of CYP3A4 (avoid
with ketoconazole, itraconazole and ritonavir).
l UNLICENSED USE g Sildenafil is used for the treatment
of digital ulcer, l but is not licensed for this indication.
Genito-urinary system
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GENERAL CONTRA-INDICATIONS
Hereditary degenerative retinal disorders. history of non-
arteritic anterior ischaemic optic neuropathy. recent
history of myocardial infarction. recent history of stroke
SPECIFIC CONTRA-INDICATIONS
▶When used for erectile dysfunction Avoid if systolic blood
pressure below 90 mmHg (no information available).
patients in whom vasodilation or sexual activity are
inadvisable. recent unstable angina
▶When used for pulmonary arterial hypertension Sickle-cell
anaemia
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GENERAL CAUTIONS Active peptic ulceration. anatomical
deformation of the penis (e.g. angulation, cavernosal
fibrosis, Peyronie’s disease). autonomic dysfunction.
bleeding disorders. cardiovascular disease. left ventricular
outflow obstruction. predisposition to priapism (e.g. in
sickle-cell disease, multiple myeloma, or leukaemia)
SPECIFIC CAUTIONS
▶When used for pulmonary arterial hypertension Hypotension
(avoid if systolic blood pressure below 90 mmHg).
intravascular volume depletion. pulmonary veno-
occlusive disease
CAUTIONS, FURTHER INFORMATION
▶Elderly For phosphodiesterase type-5 inhibitors,
prescription potentially inappropriate (STOPP criteria) in
severe heart failure characterised by hypotension i.e.
systolic blood pressure less than 90 mmHg, or concurrent
nitrate therapy for angina (risk of cardiovascular collapse).
See also Prescribing in the elderly p. 33.
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Scottish Medicines Consortium (SMC) decisions
The Scottish Medicines Consortium has advised (February
2010) that sildenafil tablets (Revatio ®) is accepted for
restricted use within NHS Scotland and should be initiated
for patients with pulmonary arterial hypertension only by
specialists in the Scottish Pulmonary Vascular Unit or
other similar specialists.
The Scottish Medicines Consortium has advised (March
2011) that sildenafil injection (Revatio ®) is accepted for
restricted use within NHS Scotland for patients with
pulmonary arterial hypertension who are currently
prescribed oral sildenafil and are temporarily unable to
take oral medicine, and should be prescribed only on the
advice of specialists in the Scottish Pulmonary Vascular
Unit or the Scottish Adult Congenital Cardiac Service.
Viagra ® is not prescribable in NHS
NHS restrictions
primary care for treatment of erectile dysfunction except
in men who meet the criteria listed in part XVIIIB of the
Drug Tariff (Part XIb of the Northern Ireland Drug Tariff,
Part 12 of the Scottish Drug Tariff). The prescription must
be endorsed ’SLS’. For more information see Prices in the
BNF, under How to use the BNF.
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