Terazosin (Hytrin) - Uses, Dose, Side effects

Terazosin (Hytrin) is an orally available medicine that acts on the alpha receptors. It is used to treat the obstructive symptoms associated with an enlarged prostate. It is occasionally used for the treatment of hypertension.

Indications of Terazosin:

  • Benign prostatic hyperplasia:

    • It is used for the treatment of symptomatic benign prostatic hyperplasia.
  • Hypertension:

    • It is indicated for the management of hypertension as an alternate agent.
  • Off Label Use in Adults:

    • Ureteral calculi expulsion

Terazosin dose in Adults

Terazosin dose in the treatment of Benign prostatic hyperplasia:

  • Initial dosage is 1 mg taken orally at bedtime; thereafter, dosage may be increased if necessary over a period of weeks while balancing therapeutic benefit with postural hypotension brought on by terazosin. The majority of individuals need 10 mg once day.
  • The maximum daily dosage is 20 mg.

Terazosin dose in the treatment of Hypertension as an alternative agent:

  • To prevent hypotension, start with a dose of 1 mg per mouth once day at bedtime. Based on the patient's reaction, titrate as necessary up to a dose of 20 mg per day in 1 or 2 divided doses.

Terazosin dose in the treatment of Ureteral calculi expulsion:

  • It can be used as a supplementary therapy to shock wave lithotripsy, taking 2 to 5 mg every oral at bedtime for up to 2 weeks or till stone evacuation.

Terazosin dose in Children

Terazosin dose in the treatment of Hypertension:

  • Children and Adolescents: Limited data available:

    • Initial: 1 mg per oral once a day, typically administered at bedtime;
    • slowly increase the dose to achieve desired blood pressure as tolerated.
    • The maximum daily dose: 20 mg/day.

Pregnancy Risk Factor C

  • Animal studies did not reveal any adverse outcomes.
  • It should not be used as a first-line medication for hypertension during pregnancy.

Use during breastfeeding:

  • If hytrin is present in breast milk is unknown.
  • Breastfeeding women are advised to use the medication with caution, according to the company.

Dose adjustment in renal disease:

  • No change in dose is required.

Hemodialysis:

  • 10% dialyzable; supplemental dose not necessary.

Hytrin Dose adjustment in liver disease:

  • There are no dosage adjustments provided in the manufacturer’s labeling.

Common Side Effects of Terazosin (Hytrin):

  • Central nervous system:

    • Dizziness
    • Myasthenia Gravis

Uncommon Side Effects of Terazosin (Hytrin):

  • Cardiovascular:

    • Peripheral Edema
    • Orthostatic Hypotension
    • Palpitations
    • Tachycardia
    • Syncope
  • Central Nervous System:

    • Drowsiness
    • Paresthesia
    • Vertigo
  • Endocrine & Metabolic:

    • Decreased Libido
    • Weight Gain
  • Gastrointestinal:

    • Nausea
  • Genitourinary:

    • Impotence
  • Neuromuscular & Skeletal:

    • Limb Pain
    • Back Pain
  • Ophthalmic:

    • Blurred Vision
  • Respiratory:

    • Nasal Congestion
    • Dyspnea
    • Sinusitis

Contraindication to Terazosin (Hytrin):

Hypersensitivity to any drug or component of the formulation

Warnings and precautions

  • CNS depression:

    • Hytrin can cause depression in the central nervous system, which could lead to mental or physical impairments.
    • It is important to warn patients about driving or operating machinery.
  • Floppy iris syndrome:

    • Alpha-blocker users who underwent cataract surgery displayed intra-operative foolish iris syndrome.
  • Syncope/orthopastatic hypotension:

    • It can cause severe orthostatic hypotension or syncope, particularly if it is administered in the initial few days.
  • Priapism

    • Although priapism is rare, Hytrin can cause it. Medical assistance is needed for any erections that last more than four hours.
  • Heart failure:

    • It can also aggravate underlying myocardial dysfunction.

Terazosin: Drug Interaction

Risk Factor C (Monitor therapy)

Alpha-/Beta-Agonists

The vasoconstricting effects of Alpha-/BetaAgonists may be lessened by Alpha1-Blockers. The vasodilation caused by Alpha1-Blocker may also be resisted by Alpha-/Beta-Agonists.

Alpha1-Agonists

Alpha1-Blockers may diminish the vasoconstricting effect of Alpha1-Agonists. Similarly, Alpha1-Agonists may antagonize Alpha1-Blocker vasodilation.

Amphetamines

May diminish the antihypertensive effect of Antihypertensive Agents.

Antipsychotic Agents (Second Generation [Atypical])

Blood Pressure Lowering Agents may enhance the hypotensive effect of Antipsychotic Agents (Second Generation [Atypical]).

Barbiturates

May enhance the hypotensive effect of Blood Pressure Lowering Agents.

Benperidol

May enhance the hypotensive effect of Blood Pressure Lowering Agents.

Beta-Blockers

May enhance the orthostatic hypotensive effect of Alpha1-Blockers. The risk associated with ophthalmic products is probably less than systemic products. Exceptions: Levobunolol; Metipranolol.

Brigatinib

May diminish the antihypertensive effect of Antihypertensive Agents. Brigatinib may enhance the bradycardic effect of Antihypertensive Agents.

Brimonidine (Topical)

May enhance the hypotensive effect of Blood Pressure Lowering Agents.

Calcium Channel Blockers

Alpha1-Blockers may enhance the hypotensive effect of Calcium Channel Blockers.

Dapoxetine

May enhance the orthostatic hypotensive effect of Alpha1-Blockers.

Dexmethylphenidate

May diminish the therapeutic effect of Antihypertensive Agents.

Diazoxide

May enhance the hypotensive effect of Blood Pressure Lowering Agents.

DULoxetine

Blood Pressure Lowering Agents may enhance the hypotensive effect of DULoxetine.

Herbs (Hypertensive Properties)

May diminish the antihypertensive effect of Antihypertensive Agents.

Herbs (Hypotensive Properties)

May enhance the hypotensive effect of Blood Pressure Lowering Agents.

Hypotension-Associated Agents

Blood Pressure Lowering Agents may enhance the hypotensive effect of Hypotension-Associated Agents.

Levodopa-Containing Products

Blood Pressure Lowering Agents may enhance the hypotensive effect of Levodopa-Containing Products.

Lormetazepam

May enhance the hypotensive effect of Blood Pressure Lowering Agents.

Methylphenidate

May diminish the antihypertensive effect of Antihypertensive Agents.

Molsidomine

May enhance the hypotensive effect of Blood Pressure Lowering Agents.

Nicorandil

May enhance the hypotensive effect of Blood Pressure Lowering Agents.

Nitroprusside

Blood Pressure Lowering Agents may enhance the hypotensive effect of Nitroprusside.

Pentoxifylline

May enhance the hypotensive effect of Blood Pressure Lowering Agents.

Pholcodine

Pholcodine's hypotensive impact may be strengthened by blood pressure lowering medications.

Prostacyclin Analogues

May enhance the hypotensive effect of Blood Pressure Lowering Agents.

Quinagolide

May enhance the hypotensive effect of Blood Pressure Lowering Agents.

Rilmenidine

Alpha1-Blockers may enhance the hypotensive effect of Rilmenidine.

Yohimbine

May diminish the antihypertensive effect of Antihypertensive Agents.

Risk Factor D (Consider therapy modification)

Amifostine

Amifostine's hypotensive impact may be strengthened by blood pressure lowering medications. Treatment: Blood pressure-lowering drugs need to be avoided for 24 hours before amifostine is administered when used at chemotherapeutic doses. Amifostine should not be given if blood pressure lowering treatment cannot be stopped.

Obinutuzumab

The hypotensive effects of blood pressure-lowering medications may be strengthened. Management: Take into account temporarily stopping blood pressure-lowering drugs 12 hours before the start of the obinutuzumab infusion and keeping them off until 1 hour after the infusion is finished.

Phosphodiesterase 5 Inhibitors

May enhance the hypotensive effect of Alpha1-Blockers (Nonselective). Management: Ensure patient is stable on one agent prior to initiating the other, and always initiate combination using the lowest possible dose of the drug being added. When tadalafil is used for treatment of BPH, concurrent alpha 1-blockers are not recommended.

Risk Factor X (Avoid combination)

Alpha1-Blockers

May enhance the antihypertensive effect of other Alpha1-Blockers.

Bromperidol

Blood Pressure Lowering Agents may enhance the hypotensive effect of Bromperidol. Bromperidol may diminish the hypotensive effect of Blood Pressure Lowering Agents.

Monitoring parameters:

  • BP in standing,sitting and supine position and at regular intervals throughout therapy
  • Urinary symptoms

How to administer Terazosin (Hytrin)?

  • It should be given orally at the same time each day.

Mechanism of action of Hytrin:

  • Hytrin, an alpha-blocking drug that allows peripheral postsynaptic blocking to result in arterial tone reduction, maintaining the negative feedback loop that is mediated through the peripheral presynaptic beta-receptors.
  • It relaxes the smooth muscle in the bladder neck, reducing obstruction at the bladder outlet.

The onset of action:

  • Antihypertensive effect: 15 minutes
  • Peak effect: Antihypertensive effect: 2 to 3 hours

Duration of action:

  • Antihypertensive effect: 24 hours

Absorption:

  • Rapid and complete

Protein binding:

  • 90% to 94%

Metabolism:

  • Occurs in the liver, minimal first-pass

Half-life elimination:

  • 12 hours

Time to peak plasma concentration:

  • 1 hour; delayed 40 minutes with food

Excretion:

  • Feces (60%, 20% as unchanged drug)
  • urine (40%, 10% as unchanged drug)

Terazosin Brand Names (International):

  • APO-Terazosin
  • DOM-Terazosin
  • Hytrin
  • MYLAN-Terazosin
  • PHL-Terazosin
  • PMS-Terazosin
  • TEVA-Terazosin
  • Adecur
  • Adenex
  • Alfaprost
  • Andrin
  • Benaprost
  • Conmy
  • Deflox
  • Eglidon
  • Flotrin
  • Hykor
  • Hyron
  • Hytracin
  • Hytrin
  • Hytrin BPH
  • Hytrine
  • Hytrinex
  • Hytroz
  • Hyzin
  • Itrin
  • Kinzosin
  • Kozosin
  • Lontencin
  • Magnurol
  • Mayul
  • Olyster
  • Prostera
  • Prostol
  • Ralsin
  • Rosyn
  • Setegis
  • Sinalfa
  • Sinraz
  • Sutif
  • Teracin
  • Teradrin
  • Teragen
  • Teralfa
  • Terapam
  • Terasin
  • Terastat
  • Terazoflo
  • Terazon
  • Terazopress
  • Terazosab
  • Tracin
  • Trasin
  • Tructum
  • Vasomet
  • Vicard
  • Zytrin

Terazosin Brands in Pakistan:

Terazosin 1 mg Tablets

Hyrox Panacea Pharmaceuticals
Hytrin Abbott Laboratories (Pakistan) Limited.
Hyzosin English Pharmaceuticals Industries
Lopros Standpharm Pakistan (Pvt) Ltd.
Setegis Medimpex Scientific Office
Tera-One Cirin Pharmaceuticals (Pvt) Ltd.
Veselo Nabiqasim Industries (Pvt) Ltd.

 

Terazosin 2 mg Tablets

Hyrox Panacea Pharmaceuticals
Hytrin Abbott Laboratories (Pakistan) Limited.
Hyzosin English Pharmaceuticals Industries
Lopros Standpharm Pakistan (Pvt) Ltd.
Ranocin Wns Field Pharmaceuticals
Razosin Welmark Pharmaceuticals
Rozacin Global Pharmaceuticals
Setegis Medimpex Scientific Office
Tera-One Cirin Pharmaceuticals (Pvt) Ltd.
Tezim Genome Pharmaceuticals (Pvt) Ltd
Veselo Nabiqasim Industries (Pvt) Ltd.

 

Terazosin 5 mg Tablets

Hyrox Panacea Pharmaceuticals
Hytrin Abbott Laboratories (Pakistan) Limited.
Hyzosin English Pharmaceuticals Industries
Lopros Standpharm Pakistan (Pvt) Ltd.
Ranocin Wns Field Pharmaceuticals
Razosin Welmark Pharmaceuticals
Rozacin Global Pharmaceuticals
Setegis Medimpex Scientific Office
Tera-One Cirin Pharmaceuticals (Pvt) Ltd.
Tezim Genome Pharmaceuticals (Pvt) Ltd