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Hytrin BPH 5 mg Tablets


Active: Terazosin 5.0
as monohydrochloride dehydrate







Therapeutic indications
Orally administered Hytrin BPH is indicated as a therapy for the symptomatic
treatment of urinary obstruction caused by benign prostatic hyperplasia (BPH).
Terazosin is a selective post synaptic alpha-1-adrenoreceptor antagonist. Antagonism
of alpha-1-receptors on prostatic and urethral smooth muscle has been shown to
improve urinary tract flow and relieve the urinary obstruction caused by BPH.


Posology and method of administration
Adults Only:
The dose of terazosin should be adjusted according to the patient's response. The
following is a guide to administration:

Initial dose
1 mg before bedtime is the starting dose for all patients and should not be exceeded.
Strict compliance with this recommendation should be observed to minimise acute
first-dose hypotensive episodes.
Subsequent dose
The dose may be increased by approximately doubling at weekly or bi-weekly
intervals to achieve the desired reduction in symptoms. The maintenance dose is
usually 5 to 10 mg once daily. Improvements in symptoms have been detected as
early as two weeks after starting treatment with terazosin.
At present there are insufficient data to suggest additional symptomatic relief with
doses above 10 mg once daily.
Treatment should be initiated using the Hytrin BPH Starter Pack and response to
treatment reviewed at four weeks. Transient side effects may occur at each titration
step. If any side effects persist, consideration should be given to reducing the dose.

Use in renal insufficiency
Pharmacokinetic studies indicate that patients with impaired renal function need no
alteration in the recommended dosages.

Use in Children
Use in children for BPH is not applicable.
Use in the Elderly
Pharmacokinetic studies in the elderly indicate that no alteration in dosage
recommendation is required.
Postural Hypotension
Postural hypotension has been reported to occur in patients receiving terazosin for the
symptomatic treatment of urinary obstruction caused by BPH. In these cases, the
incidence of postural hypotensive events was greater in patients aged 65 years and
over (5.6%) than those aged less than 65 years (2.6%)


Terazosin is contraindicated in patients known to be hypersensitive to alphaadrenoreceptor antagonists.


Special warnings and precautions for use
Concomitant use of phosphodiesterase-5-inhibitors (e.g. sildenafil, tadalafil,
vardenafil) and Terazosin may lead to symptomatic hypotension in some patients. In
order to minimise the risk for developing postural hypotension the patient should be
stable on the alpha-blocker therapy before initiating use of phosphodiesterase-5inhibitors.
In patients with benign prostatic hyperplasia Terazosin is not recommended for
patients with a history of micturition syncope.
Terazosin decreases peripheral vascular resistance and since many patients with this
disorder are elderly, careful monitoring of blood pressure during initial administration
and during adjustment of dosage is recommended. The possibility of postural
hypotension, or rarely, loss of consciousness, as reported in other patient groups
should be borne in mind. Close observation is especially recommended. For patients
taking medications that are known to lower blood pressure, Terazosin may augment
the efficacy of antihypertensive therapy, consequently, close observation is especially
recommended for patients taking medications that are known to lower blood pressure.
Terazosin should not normally be administered to patients already receiving another
Sudden collapse may follow the initial dose of Terazosin.
In patients with congestive cardiac failure Terazosin is not recommended in the
treatment of congestive cardiac failure due to mechanical obstruction such as aortic
valve stenosis, mitral valve stenosis, pulmonary embolism and restrictive pericardial
disease. Adequate data are not yet available to establish efficacy in patients with heart
failure due to recent myocardial infarction.
When Terazosin is initially administered to patients with congestive cardiac failure
who have undergone vigorous diuretic or other vasodilator treatment, particularly in
higher than the recommended starting dose, the resultant decrease in left ventricular
filling pressure may be associated with a significant fall in cardiac output and
systemic blood pressure. In such patients, observance of the recommended starting
dose of Terazosin followed by gradual dosage increase is particularly important.
The clinical efficacy of Terazosin in congestive cardiac failure has been reported to
diminish after several months of treatment, in a proportion of patients. In these
patients there is usually evidence of weight gain or peripheral oedema indicating fluid
retention. Since spontaneous deterioration may occur in such severely ill patients, a

causal relationship to Terazosin therapy has not been established. Thus, as with all
patients with congestive cardiac failure, careful adjustment of diuretic dosage
according to the patient's clinical condition is required to prevent excessive fluid
retention and consequent relief of symptoms.
In those patients without evidence of fluid retention, when clinical improvement has
diminished, an increase in the dosage of Terazosin will usually restore clinical
In patients with hypertension A very small percentage of patients may respond in an
abrupt and exaggerated manner to the initial dose of Terazosin. Postural hypotension
evidenced by dizziness and weakness, or rarely loss of consciousness, has been
reported, particularly with the commencement of therapy, but this effect is readily
avoided by initiating treatment with a low dose of Terazosin and with small increases
in dosage during the first one to two weeks of therapy. The effect when observed is
not related to the severity of hypertension, is self-limiting and in most patients does
not recur after the initial period of therapy or during subsequent titration steps.


Interaction with other medicinal products and other forms of interaction
In patients receiving terazosin plus ACE inhibitors or diuretics the proportion
reporting dizziness or related side effects was greater than in the total population of
terazosin treated patients from clinical trials.
Caution should be observed when terazosin is administered with other
antihypertensive agents, to avoid the possibility of significant hypotension. When
adding terazosin to a diuretic or other antihypertensive agent, dosage reduction and
retitration may be necessary.
Terazosin has been given without interaction with analgesics/anti-inflammatories,
cardiac glycosides, hypoglycemics, antiarrhythmics, anxiolytics/sedatives,
antibacterials, hormones/steroids and drugs used for gout.
Phosphodiesterase-5-inhibitors (e.g. sildenafil, tadalafil, vardenafil) (see section 4.4).


Pregnancy and lactation
Although no teratogenic effects were seen in animal testing, the safety of
Hytrin use during pregnancy or during lactation has not yet been established.
Hytrin should not be used therefore in pregnancy unless the potential benefit
outweighs the risk.


Effects on ability to drive and use machines
Dizziness, light-headedness or drowsiness may occur with the initial dose or in
association with missed doses and subsequent reinitiation of Hytrin therapy.
Patients should be cautioned about these possible adverse effects and the
circumstances in which they may occur and advised to avoid driving or
hazardous tasks for approximately 12 hours after initial dose or when the dose
is increased.


Undesirable effects
Hytrin in common with other alpha-adrenoceptor antagonists may cause
syncope. Syncopal episodes have occurred within 30 to 90 minutes of the
initial dose of the drug. Syncope has occasionally occurred in association with
rapid dosage increases or the introduction of another antihypertensive agent.
In clinical trials in hypertension, the incidence of syncopal episodes was
approximately one percent. In most cases this was believed to be due to an
excessive postural hypotensive effect although occasionally the syncopal
episode has been preceded by a bout of tachycardia with heart rates of 120 to
160 beats per minute.
If syncope occurs the patient should be placed in a recumbent position and
supportive treatment applied as necessary.
Dizziness, light-headedness or fainting may occur when standing up quickly
from a lying or sitting position. Patients should be advised of this possibility
and instructed to lie down if these symptoms appear and then sit for a few
minutes before standing to prevent their recurrence.
These adverse effects are self limiting and in most cases do not recur after the
initial period of therapy or during subsequent re-titration.
Adverse events reported with terazosin
The most common events were asthenia, palpitations, nausea, peripheral
oedema, dizziness, somnolence, nasal congestion/rhinitis and blurred
In addition, the following have been reported: back pain; headache;
tachycardia; postural hypotension; syncope; oedema; weight gain; pain in
extremities; decreased libido; depression; nervousness; paraesthesia; vertigo;
dyspnoea; sinusitis and impotence.
Additional adverse reactions reported in clinical trials or reported during
marketing experience but not clearly associated with the use of terazosin
include the following:

chest pain; facial oedema; fever; abdominal pain; neck pain; shoulder pain;
vasodilation; arrhythmia; constipation; diarrhoea; dry mouth; dyspepsia;
flatulence; vomiting; gout; arthralgia; arthritis; joint disorders; myalgia;
anxiety; insomnia; bronchitis; epistaxis; flu symptoms; pharyngitis; rhinitis;
cold symptoms; pruritis; rash; increased cough; sweating; abnormal vision;
conjunctivitis; tinnitus; urinary frequency; urinary tract infection and urinary
incontinence primarily reported in post-menopausal women.
At least two cases of anaphylactoid reactions have been reported with the
administration of terazosin.
Post marketing experience: Thrombocytopenia and priapism have been
reported. Atrial fibrillation has been reported: however, a cause and effect
relationship has not been established.
Laboratory tests: Small but statistically significant decreases in haematocrit,
haemoglobin, white blood cells, total protein and albumin were observed in
controlled clinical trials. These laboratory findings suggest the possibility of
haemodilution. Treatment with terazosin for up to 24 months had no
significant effect on prostate specific antigen (PSA) levels.

Should administration of Hytrin lead to acute hypotension, cardiovascular
support is of first importance. Restoration of blood pressure and normalisation
of heart rate may be accomplished by keeping the patient in a supine position.
If this measure is inadequate, shock should first be treated with volume
expanders and if necessary, vasopressors could then be used. Renal function
should be monitored and general supportive measures applied as required.
Dialysis may not be of benefit since laboratory data indicate that terazosin is
highly protein bound.




Pharmacodynamic properties
Studies suggest that alpha-1-adrenoreceptor antagonism is useful in improving the
urodynamics in patients with chronic bladder obstruction such as in benign prostatic
hyperplasia (BPH).
The symptoms of BPH are caused mainly by the presence of an enlarged prostate and
by the increased smooth muscle tone of the bladder outlet and prostate, which is
regulated by alpha-1-adrenergic receptors.

In in-vitro experiments, Hytrin has been shown to antagonise phenylephrine-induced
contractions of human prostatic tissue. In clinical trials Hytrin has been shown to
improve the urodynamics and symptomatology in patients with BPH


Pharmacokinetic properties
The plasma concentration of the parent drug is a maximum about 1 hour post
administration and declines with a half-life of approximately 12 hours. Food
has little or no effect on bioavailability. Approximately 40% of the
administered dose is eliminated in the urine and 60% in the faeces. The drug is
highly bound to plasma proteins.


Preclinical safety data
Carcinogenicity: Hytrin has been shown to produce tumours in male rats when
administered at a high dose over a long period of time. No such occurrences
were seen in female rats or in a similar study in mice. The relevance of these
findings with respect to the clinical use of the drug in man is unknown.




List of excipients
Lactose, maize starch, pregelatinised starch, purified talc, magnesium stearate
and purified water.


None known.


Shelf life
36 months.


Special precautions for storage


Nature and contents of container
Tablets in a blister pack. The 1mg tablets are only available as part of a starter pack.
The starter pack consists of 7 x 1mg, 14 x 2mg and 7 x 5mg tablets. The blisters, of
PVC/PVdC, are heat sealed with 20 micron hard tempered aluminium foil and
packaged in a carton with a pack insert.


Special precautions for disposal
Not applicable.


Amdipharm PLC
Regency House
Miles Gray Road
SS14 3AF
United Kingdom


PL 20072/0034





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