MALEREPRODUCTIVEENDOCRINOLOGY 315significant proportion of men who receive placebo discontinue
their participation because of the occurrence of impotence which
they attribute to therapy. Drugs that affect the autonomic supply
to the sex organs are not alone in interfering with sexual function.
Indeed,bendroflumethiazide, a thiazide diuretic, caused signif-
icantly more impotence in the Medical Research Council (MRC)
trial of mild hypertension than did propranolol, a β-adrenocep-
tor antagonist. Drugs that do interfere with autonomic function
and can also cause erectile dysfunction include phenothiazines,
butyrophenones and tricyclic antidepressants. Pelvic non-adren-
ergic, non-cholinergic nerves are involved in erectile function
and utilize nitric oxide as their neurotransmitter. Nitric oxide
release from endothelium in the corpus cavernosum is abnormal
in some cases of organic impotence, e.g. in diabetes mellitus.
Phosphodiesterase type 5 inhibitors licensed for the treat-
ment of erectile dysfunction include sildenafil,tadalafiland
vardenafil. They have revolutionized the treatment of erectile
dysfunction. Caution is needed in patients with cardiovascular
disease, anatomical deformation of the penis, e.g. Peyronie’s dis-
ease, and in those with a predisposition to prolonged erection,
e.g. in sickle-cell disease. They are contraindicated in patients
who are on nitrates and in patients with a previous history of
non-arteritic anterior ischaemic optic neuropathy.
The side effects include dyspepsia, vomiting, headache,
flushing, dizziness, myalgia, visual disturbances, raised intra-
ocular pressure and nasal congestion.
Other therapeutic options for erectile dysfunction include
intracavernosal injection or urethral application of alprostadil
(prostaglandin E 1 ). Priapism and hypotension are side effects.
Any treatment for erectile dysfunction should only be initiated
after treatable medical causes have been excluded.
A few cases of reduced libido and impotence in males and
females are associated with idiopathic hyperprolactinaemia, and
in such cases bromocriptinemay restore potency. Androgens
play a role in both male and female arousal, but their use is not
appropriate except in patients with reduced circulating concen-
trations of testosterone.
FURTHER READING
Baird DT, Glasier AF. Science, medicine, and the future:
Contraception.British Medical Journal1999; 319 : 969–72.
Nelson HD. Assessing benefits and harms of hormone replacement
therapy: clinical applications. Journal of the American Medical
Association2002; 288 : 882–4.
Nelson HD, Humphrey LL, Nygren P et al. Postmenopausal hormone
replacement therapy: scientific review. Journal of the American
Medical Association2002; 288 : 872–81.
US Preventive Services Task Force. Hormone therapy for the preven-
tion of chronic conditions in postmenopausal women: recommen-
dations from the US Preventive Services Task Force. Annals of
Internal Medicine2005; 142 : 855–60.
Wathen CN, Feig DS, Feightner JW et al. and The Canadian Task Force
on Preventive Health Care. Hormone replacement therapy for the
primary prevention of chronic diseases: recommendation state-
ment from the Canadian Task Force on Preventive Health Care.
Canadian Medical Association Journal2004; 170 : 1535–7.Case history
A 26-year-old woman consults you in your GP surgery
regarding advice about starting the combined oral contra-
ceptive pill.
Question
Outline your management of this patient.
Answer
It is very important to take a careful history in order to exclude
any risk factors which would contraindicate the combined oral
contraceptive, such as a past history of thrombo-embolic dis-
ease or risk factors for thrombo-embolic disease. In addition, it
is important to ascertain whether the patient is a smoker and
when she last had a cervical smear. It is important to exclude
a history of migraine and to check her blood pressure.
The combined oral contraceptive is probably an appropri-
ate form of contraception in a woman of this age, who would
possibly be highly fertile, as it is the most reliable form of con-
traception available, provided that there are no risk factors to
contraindicate the combined oral contraceptive. There are
many COCs on the market and selection for this individual
would be dependent on a balance of achieving good cyclecontrol and weighing the beneficial effects on plasma lipids
offered by the newer progestogens, such as desogestrel,
gestadine and norgestimate, against the recently reported
two-fold increased risk of venous thrombo-embolism noted
with desogestrel and gestadine. In a woman of this age, the
beneficial effects on plasma lipids are probably of minor
importance and in view of the increased risk of venous
thrombo-embolism it would probably be appropriate to
choose a pill containing norethisterone, levonorgestrel or
norgestimate. The majority of women achieve good cycle con-
trol with combined oral contraceptives containing oestrogen
at a dose of about 30–35μg; pills containing the higher dose
of oestrogen would only be required if the individual was on
long-term enzyme-inducing therapy (e.g. rifampicin) or anti-
convulsant medication.Case history
A 50-year-old woman consults you about her symptoms
of flushing and vaginal discomfort. She is thin and is a
smoker.
Question
Outline the therapy most likely to be of benefit, including
the reasons for this.
Answer
This woman is probably menopausal and is suffering the
consequences of the vasomotor effects of the menopause, as
well as vaginal dryness. The vaginal dryness could be treated
locally with short periods of treatment with topical oestro-
gens. However, in view of her other symptoms, a better
option would be to start her on hormone replacement ther-
apy. If she still has an intact uterus then it is important to give
both oestrogen and cyclical progestogen to protect the
endometrium from hyperplasia. Depending on preference,
life-style and the likelihood of compliance, either oral ther-
apy or patches may be appropriate. In this woman, who has
risk factors for osteoporosis, such as smoking and thinness, it
may be of benefit to continue the hormone replacement
therapy for a period of at least five years and possibly longer,
although it is important to exercise caution with regard to
her risk for breast cancer and cardiovascular disease.