Korea United Pharma


Pharma 3
Full Prescribing Info
Terazosin HCl.
Alpha-adrenoceptor blocker.
Management of mild to moderate hypertension and benign prostatic hypertrophy (BPH) to relieve urinary obstruction.
Dosage/Direction for Use
Adults: Initial Dose: 1 mg at bedtime is the starting dose for all patients and this dose should not be exceeded as an initial dose. Patients should be closely followed-up during initial administration in order to minimize the risk of severe hypotensive response.
Maintenance Dose: Hypertension: Single Dose: 2-10 mg once a day in the morning or evening and should be adjusted to same time as usual. For desired blood pressure response, the dosage may be increased gradually. Doses >20 mg do not appear to provide further blood pressure effect and doses >40 mg have not been studied.
Concomitant administration with thiazide diuretics and other antihypertensive agents: Caution should be observed when terazosin HCl is administered concomitantly with other antihypertensive agents, especially the calcium-channel blocker verapamil, to avoid the possibility of developing significant hypotension. When using terazosin HCl and other antihypertensive agents concomitantly, dosage reduction and retitration of either agent may be necessary (see Precautions).
Benign Prostatic Hyperplasia: Usual Maintenance Dose: 5-10 mg once daily. The dose is increased gradually according to the patient's age and response. To achieve the desired improvement in symptoms as terazosin HCl, subsequent dosage may be increased in a stepwise manner.
Administration: If other drugs are inadequate or ineffective, terazosin HCl can be used alone or in combination with other thiazide diuretics or antihypertensive agents.
Hykor can be administered regardless of meals, because food does not affect bioavailability of terazosin HCl particularly at all.
The dose of terazosin HCl should be adjusted according to blood pressure response and tolerance.
Should overdosage of terazosin HCl lead to hypotension, support of the cardiovascular system is of 1st importance. Restoration of blood pressure and normalization of heart rate may be accomplished by keeping the patient in the supine position. If this measure is inadequate, shock should 1st be treated with volume expanders. If necessary, vasopressors should then be used and renal function should be monitored and supported as necessary. Laboratory data indicate that terazosin is 90-94% protein bound; therefore, dialysis may not be of benefit.
Patients with known hypersensitivity to α-blockers or terazosin HCl. Children <12 years.
Special Precautions
Patients should be made aware of the possibility of syncopal and orthostatic symptoms, especially at the initiation of therapy and to avoid driving or hazardous tasks for 12 hrs after the 1st dose, after a dosage increase and after interruption of therapy when treatment is resumed. They should be cautioned to avoid situations where injury could result, should syncope occur during initiation of terazosin therapy. They should also be advised of the need to sit or lie down when symptoms of lowered blood pressure occur, although these symptoms are not always orthostatic and to be careful when rising from a sitting or lying position. If dizziness, lightheadedness or palpitations are bothersome, they should be reported so that dose adjustment can be considered.
The possibility of carcinoma of the prostate and other conditions associated with manifestations that mimic those of BPH should be excluded in any patient for whom terazosin therapy for presumed BPH is being considered.
Patients with severe impairment of liver and renal function.
Terazosin should be administered with caution in the following patients: Orthostatic hypotension, seizure, asphyxia, myocardial infarction, cerebrovascular dysfunction, transient ischemic attack, angina, gastric ulcer, alcohol poisoning, other liver disease, retinitis hypertonica (type III and IV), insulin-dependent diabetes mellitus.
Use in pregnancy: There are no adequate and well-controlled studies in pregnant women and the safety of terazosin in pregnancy has not been established. Terazosin HCl is not recommended during pregnancy unless the potential benefit justifies the potential risk to the mother and fetus.
Use in lactation: Since it is not known whether terazosin is distributed into milk, Hykor should be used with caution in nursing women.
Use in children: Safety and effectiveness in pediatric patients have not been established.
Use in the elderly: Geriatric patients (eg, ≥65 years) may be particularly susceptible to postural as well as certain other adverse effects of terazosin. While the manufacturer makes no specific recommendations for titration of terazosin dosage in geriatric patients, patients in this age group generally are less tolerant of the postural hypotensive effects of α1-adrenergic blocking agents because of impaired cardiovascular reflexes and caution should be exercised. Therefore, dosage escalation in elderly patients generally should be slower than younger adults (The initial dosage of terazosin is 0.25 mg twice daily). Because of their susceptibility to hypotension, assessment of blood pressure response in both the standing and sitting (or supine) positions is important when Hykor is used to treat hypertension in this age group.
Use In Pregnancy & Lactation
Use in pregnancy: There are no adequate and well-controlled studies in pregnant women and the safety of terazosin in pregnancy has not been established. Terazosin HCl is not recommended during pregnancy unless the potential benefit justifies the potential risk to the mother and fetus.
Use in lactation: Since it is not known whether terazosin is distributed into milk, Hykor should be used with caution in nursing women.
Adverse Reactions
Adverse effects due to the use of terazosin are mild to moderate.
Terazosin, like other α-blocking agents, can cause syncope (clinical manifestation rate: About 1%). Occasionally, syncopal episodes have been preceded by episodes of severe tachycardia with heart rate of 120-160 beats per minute, but mostly severe orthostatic hypotension may be accompanied. Syncope has been reported within 30-90 min after administering initial dose. It has also been reported in association with rapid dosage increases. If syncope occurs, the patient should be placed in a recumbent position and treated supportively as necessary. Because this adverse reaction is self-controlled, it may not reoccur after administering initial dose or during dosage increases.
In patients exceeding up to 40 mg dose of terazosin, dizziness, energy deficiency and peripheral edema generally occurs. Mostly, this adverse reaction is reduced by sustained therapy or is tolerated without dosage decreases.
Central Nervous System: Depression, hypersensitivity, occasionally headache, dizziness, cenesthopathy, debility, sweating, insomnia, frigidity and shoulder stiffness, rarely drowsiness and numbness may occur.
Circulatory System: Tachycardia, vasodilation, occasionally orthostatic dysregulation, cardiopalmus edema, arrhythmia (extrasystole, atrial fibrillation, etc), cardialgia, rarely cardiagra, tachycardia may occur.
Hepatic: Occasionally, AST, ALT, ALP, total bilirubin increases may occur.
Digestive System: Dyspepsia, abdominal distention, stomach disorder, occasionally abdominalgia, diarrhea, constipation, nausea and vomiting, rarely anorexia may occur.
Respiratory System: Nose bleeding, flu symptom, pharyngitis, rhinitis, dyspnea, cold symptom, nasal hyperemia, cough increase and sinusitis may occur.
Urogenital System: Occasionally oliguria, rarely incontinence (female after menopause), BUN and CPK rise may occur.
Sensory Organ: Paresthesia, balance disturbance, visual disorder, amblyopia, syndesmitis and tinnitus may occur.
Metabolism: Water retention, rarely edema may occur.
Hypersensitivity: Occasionally eruption may occur. If they occur, the administration should be discontinued.
Others: Weight increase, spasticity, arthrocus, arthrorisis asthenia, myalgia, celebitas sexualis, sweating, impotence, priapism and thrombocytopenia, occasionally erethism, stuffed nose, breathless feeling, eye sense of incompatibility and pruritus may occur. Occasionally, antinuclear antibody (ANA) positive may also occur.
Drug Interactions
In controlled trials, terazosin has been added to diuretics and several β-adrenergic blockers; no unexpected interactions were observed. Terazosin has also been used in patients on a variety of concomitant therapies; while these were not formal interaction studies, no interactions were observed. Terazosin has also been used concomitantly on the following drugs or drug classes: Analgesic/anti-inflammatory (eg, acetaminophen, aspirin, codeine, ibuprofen, tolmetin, phenylbutazone, dextropropoxyfen, indomethacin); cardiac glycoside (eg, digoxin); hypoglycemics (eg, chlorpropamide, insulin, tolazamide, tolbutamide); diluent for IV injection (eg, procainamide); sedatives and tranquilizers (eg, chlorazepate, chlorzepoxide, diazepam, flurazepam); anti-arthritic (eg, allopurinol, probenecid); antibiotics (eg, ampicillin, penicillin, tetracycline, erythromycin, trimethoprim and sulfamethoxazole); hormone/steroid (eg, estrogen agent); antihistamines (eg, chlorpheniramine); cardiovascular agents (eg, atenolol, hydrochlorothiazide, methyclothiazide, propranolol); anticholinergic/sympathomimetics (eg, phenylephrine HCl, phenylpropanolamine HCl, pseudoephedrine HCl); GI agents (eg, antacids).
Caution should be exercised when adding terazosin to a preexisting antihypertensive regimen or when adding other hypotensive agents to a terazosin regimen in order to avoid a possible rapid fall in blood pressure and exacerbation of postural effects. Dosage reduction and/or retitration of therapy may be necessary. Particular caution may be necessary when terazosin and verapamil are used concomitantly because of an added potential pharmacokinetic interaction (ie, verapamil-induced increases in plasma terazosin concentrations) (see Dosage & Administration).
Drug/Laboratory Test Interactions: Small but statistically significant decreases in hematocrit, hemoglobin, white blood cells, total protein and albumin were observed in controlled-clinical trials. These laboratory findings suggested the possibility of hemodilution. Treatment with terazosin for up to 24 months had no significant effect on prostate-specific antigen (PSA) levels.
Store at a temperature not exceeding 25°C.
ATC Classification
G04CA03 - terazosin ; Belongs to the class of alpha-adrenoreceptor antagonists. Used in the treatment of benign prostatic hypertrophy.
Tab 2 mg (light orange, round-bevelled edge, scored on one side with engraved "TN" on the other) x 100's.
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