METOLAZONE tablet

Country: United States

Language: English

Source: NLM (National Library of Medicine)

Active ingredient:

METOLAZONE (UNII: TZ7V40X7VX) (METOLAZONE - UNII:TZ7V40X7VX)

Available from:

Cardinal Health

INN (International Name):

METOLAZONE

Composition:

METOLAZONE 2.5 mg

Prescription type:

PRESCRIPTION DRUG

Authorization status:

Abbreviated New Drug Application

Summary of Product characteristics

METOLAZONE- METOLAZONE TABLET
CARDINAL HEALTH
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DO NOT INTERCHANGE: DO NOT INTERCHANGE ZAROXOLYN® TABLETS AND
OTHER FORMULATIONS OF METOLAZONE THAT SHARE ITS SLOW AND
INCOMPLETE BIOAVAILABILITY AND ARE NOT THERAPEUTICALLY EQUIVALENT
AT THE SAME DOSES TO MYKROX® TABLETS, A MORE RAPIDLY AVAILABLE AND
COMPLETELY BIOAVAILABLE METOLAZONE PRODUCT. FORMULATIONS
BIOEQUIVALENT TO ZAROXOLYN® AND FORMULATIONS BIOEQUIVALENT TO
MYKROX® SHOULD NOT BE INTERCHANGED FOR ONE ANOTHER.
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DESCRIPTION
Metolazone Tablets, USP for oral administration contain 2.5 mg, 5 mg
or 10 mg of metolazone, USP, a
diuretic/saluretic/antihypertensive drug of the quinazoline class.
Metolazone has the molecular formula C
H ClN O S, the chemical name 7-chloro-1, 2, 3, 4-
tetrahydro-2-methyl-3-(2-methylphenyl)-4-oxo-6-quinazolinesulfonamide,
and a molecular weight of
365.83. The structural formula is:
Metolazone is only sparingly soluble in water, but more soluble in
plasma, blood, alkali, and organic
solvents. Inactive Ingredients: colloidal silicon dioxide, FD&C Yellow
#6 Lake HT, magnesium
stearate and microcrystalline cellulose. In addition, the 10 mg
strength contains D&C Yellow #10 Lake
HT and FD&C Blue #2 Lake HT.
CLINICAL PHARMACOLOGY
Metolazone is a quinazoline diuretic, with properties generally
similar to the thiazide diuretics. The
actions of metolazone result from interference with the renal tubular
mechanism of electrolyte
reabsorption. Metolazone acts primarily to inhibit sodium reabsorption
at the cortical diluting site and to
a lesser extent in the proximal convoluted tubule. Sodium and chloride
ions are excreted in
approximately equivalent amounts. The increased delivery of sodium to
the distal tubular exchange site
results in increased potassium excretion. Metolazone does not inhibit
carbonic anhydrase. A proximal
action of metolazone has been shown in humans by increased excretion
of phosphate and magnesium
ions and by a markedly increased fractional excretion of sodium in
patients with severely compromised
glomerular f