VIAGRA, CIALIS OR LEVITRA TREATMENT FOR ERECTILE DYSFUNCTION FREQUENTLY-ASKED QUESTIONS

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VIAGRA, CIALIS OR LEVITRA TREATMENT
FOR ERECTILE DYSFUNCTION
FREQUENTLY-ASKED QUESTIONS
What are these drugs?
Viagra® (sildenafil), Cialis® (tadalafil) and Levitra® (vardenafil) work by using the
body’s natural mechanism to control erection. They block the naturally-occurring
enzyme, phosphodiesterase-5 (PDE-5), which “turns off” an erection. This allows
erection to be achieved and maintained more easily.
What are they used for?
These drugs are only licensed for use in men with erectile dysfunction (impotence).
They are not recommended for men with normal erections who simply wish to
improve their sexual performance. They are not licensed for use in female sexual
dysfunction. They have no effect on sexual desire (libido), ejaculation or fertility
What do they do?
The drugs boost an existing erection but
this must be achieved by sexual
stimulation. The drugs do not produce
erections in their own right.
Sexual stimulation, therefore, is an
essential part of the their action.
How should they be taken?
These tablets should be taken approximately one hour before anticipated sexual
intercourse. The maximum recommended frequency is once per day but treatment
can be continued for long periods (in excess of 12 months).
Viagra can be taken on a daily basis to provide background sexual stimulation. The
newer agents (Levitra & Cialis) are longer-lasting and only need to be taken on
alternate days for this effect. If taken as a regular prescription, treatment should be
continued for a minimum of six weeks before effectiveness can be adequately
assessed.
Your consultant, GP or specialist nurse will advise you on the starting dose and will
monitor the effect to determine whether any increase in dosage is necessary.
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Parameter
Time to maximum effect (hr)
Half-life (hr)
Sildenafil
0.8 – 1
2.6 – 3.7
Tadalafil
2
17.5
Vardenafil
0.9
3.9
When should they not be taken?
These drugs should not be taken by patients receiving treatment for angina with
organic nitrates (GTN, isosorbide or amyl nitrate). Interaction with these drugs can
cause a dangerous fall in blood pressure and may result in cardiac arrest. A similar,
but less dangerous, effect is seen with alcohol; caution should be exercised when
taking a PDE-5 inhibitor after alcohol.
These drugs should not be used when sexual activity is inadvisable, such as in men
with unstable angina or severe heart failure and they should not be used at the same
time as any other forms of treatment for erectile dysfunction.
They can be taken with food. However, the response may be delayed by a large
meal, especially one with a high fat content.
What are the side-effects?
The three most common side-effects are headache (in 12%), flushing (in 10%) and
indigestion (in 7%). Altered vision (a blue tinge) with dizziness can occur in 3%.
Some patients experience aching in muscles. Higher doses are more likely to
produce side-effects, especially muscle ache. If dizziness occurs, it is advisable not
to drive or to operate machinery.
Approximately 12% of men experience significant side-effects overall, although only
3% need to stop the treatment as a result of these side-effects:
Side-effect
Headache
Flushing
Indigestion
Nasal congestion
Dizziness
Abnormal vision
Back pain
Muscle aching
Sildenafil
12.8%
10.4%
4.6%
1.1%
1.2%
1.9%
-
Tadalafil
14.5%
4.1%
12.3%
4.3%
2.3%
6.55%
5.7%
Vardenafil
16%
12%
4%
10%
2%
<2%
-
There have been reports of sudden death, especially after the use of Viagra. Some
of these deaths have been linked to the use of nitrates. Most can be attributed to
major physical exertion, including sexual activity, carrying a degree of risk to the
heart. Many of these deaths were due to unaccustomed exertion resulting in a heart
attack or acute heart failure.
If you are in any doubt about whether it is safe to take these drugs, consult your GP
for further advice.
VIAGRA, CIALIS OR LEVITRA TREATMENT FOR ERECTILE DYSFUNCTION
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How do I get these drugs?
You can obtain a prescription from your GP. It is very unwise to purchase unlicensed
preparations through adverts in newspapers, magazines or on the web.
You may be eligible for an NHS prescription if you are suffering from certain specified
conditions but this applies to only 15 - 20% of patients. The remaining 80 - 85%
need to obtain the drugs by private prescription from their GP.
Eligible conditions for NHS prescription are:
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diabetes mellitus;
injury (spinal cord or pelvis);
multiple sclerosis;
poliomyelitis;
prostate cancer;
psychological distress (severe);
renal failure;
single-gene neurological disorders;
spina bifida; or
surgery (prostatectomy & radical
pelvic surgery).
If you have any problem obtaining a prescription, you should contact your consultant
urologist or specialist nurse directly.
Are there any other important points?
This booklet contains guidelines and advice from professional bodies, together with
information about the prescription of drugs.
All NHS hospitals have local
arrangements with their Primary Care Trusts (PCTs) about which medicines can be
used. As a result, some drugs mentioned cannot be prescribed by local hospitals.
Treatment of patients will be planned with the doctor responsible for care, taking into
account those drugs which are or are not available at the local hospital and what is
appropriate for optimum patient care.
Healthcare professionals are advised to check prescribing arrangements with their
local hospital or PCT.
Disclaimer
While we have made every effort to be sure the information in this booklet is
accurate, we cannot guarantee there are no errors or omissions. We cannot accept
responsibility for any loss resulting from something that anyone has, or has not, done
as a result of the information in this booklet.
© British Association of Urological Surgeons (BAUS) Limited
Published: March 2014
Due for review: March 2015
VIAGRA, CIALIS OR LEVITRA TREATMENT FOR ERECTILE DYSFUNCTION
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