Hydrochlorothiazide + Metoprolol

Indications

Hydrochlorothiazide + Metoprolol is used for: Hypertension

Adult Dose

Oral Hypertension metoprolol tartrate 50-100 mg and hydrochlorothiazide 25-50 mg PO daily in single or divided doses Hepatic impairment: Reduction in dose may be necessary. Severe impairment: avoid.

Child Dose

Renal Dose

Renal impairment: CrCl (ml/min) Dosage Recommendation <30 Avoid

Administration

Contra Indications

2nd or 3rd degree AV block, sinus bradycardia, cardiogenic shock, congestive heart failure; anuria; systolic hypotension (<100 mmHg); severe kidney or liver failure; therapy resistant hypokalaemia and hyponatraemia; hypercalcaemia; symptomatic hyperuricaemia; lactation.

Precautions

Renal or hepatic impairment; DM; hyperlipidaemia; hyperuricaemia; left ventricular hypertension and ventricular ectopics; thyrotoxicosis; major surgery; gradual withdrawal; pregnancy; Prinzmetal's angina; reversible obstructive airways disease; elderly; psoriasis; general anaesthesia; not recommended for initial treatment of hypertension. Lactation: excreted in breast milk, use caution

Pregnancy-Lactation

Pregnancy Category: C Lactation: excreted in breast milk, use caution

Interactions

Effects of tubocurarine may be prolonged while corticosteroids may increase the risk of hypokalaemia; may precipitate azotemia in renal patients; increased hypotensive effects with: alcohol, α-blockers, general anaesthetics, hydralazine, levodopa, MAOIs, methyldopa, nitrates, phenothiazines, ACE inhibitors, adrenergic neurone blockers, aldesleukin, alprostadil, antiotensin-II receptor antagonists, TCAs, anxiolytics and hypnotics, baclofen, calcium-channel blockers, clonidine, diazoxide, minoxidil, moxisylyte, moxonidine, sodium nitroprusside, tizanidine; hydrochlorothiazide increases plasma concentration of fluconazole; β-blockers may mask warning signs of hypoglycaemia with antidiabetics, increased hypoglycaemic effect of insulin; hypotensive effect antagonised by corticosteroids, NSAIDs, oestrogens, indomethacin, ketorolac; reduced metoprolol plasma concentration with barbiturates, rifampicin; increased metoprolol plasma concentration with cimetidine, citalopram, escitalopram, paroxetine, propafenone; hypokalaemia potentially caused by hydrochlorothiazide may antagonise action of lidocaine, mexiletine, reboxetine; increased risk of hypokalaemia with acetazolamide, amphotericin, corticosteroids, theophylline; increased risk of hyponatraemia with carbamazepine, chlorpropamide; increased risk of sensitivity with allopurinol (especially in renal impairment); increased risk of hypercalcaemia with calcium salts, toremifene, vitamin D; increased risk of hypermagnesaemia with ciclosporin (and risk of nephrotoxicity); absorption of thiazides reduced by colestipol and colestyramine (take at least 2 hr apart).

Adverse Effects

Side effects of Hydrochlorothiazide + Metoprolol : 1-10% Metoprolol tartrate Bradycardia (3%), cold extremities(1%), constipation (1%), depression (5%), diarrhea (5%), dizziness (10%), dyspepsia (1%), dyspnea (3%), fatigue (10%), headache (10%), heart failure (1%), hypokalemiahypotension (1%), influenza-like symptomsnausea (1%), pruritus (5%), wheezing (1%) Hydrochlorothiazide Anorexia, epigastric distress, hypokalemia, hypotension, phototoxicity Frequency Not Defined Metoprolol tartrate Bronchospasm, mask symptoms of hypoglycemia Hydrochlorothiazide Anaphylaxis, anemia, confusion, erythema multiforme skin reactions including Stevens-Johnson syndrome, exfoliative dermatitis including toxic epidermal necrolysis, hypomagnesemia, hyponatremia, hypochloremia, dizziness, fatigue, headache, hypercalcemia, hyperuricemia, hyperglycemia, hyperlipidemia, hypercholesterolemia, muscle weakness or cramps, nausea, purpura, rash, vertigo, vomiting

Mechanism of Action

Metoprolol is a cardioselective β-blocker causing reduction in heart rate, cardiac output and blood pressure. Hydrochlorothiazide increases renal excretion of sodium and chloride and reduces cardiac load. The two drugs exert additive effects in hypertension.