Methyclothiazide

log Kow = 1.42 at pH 6.5

0.6

0.6

Crystals form alcohol and water

White or practically white, crystalline powder

Slightly soluble in alcohol; freely soluble in acetone, pyridine; sparingly soluble in methanol; very slightly soluble in water, benzene, chloroform, isopropyl alcohol.

8.24e-01 g/L

Breast Feeding; Lactation; Milk, Human; Antihypertensive Agents; Thiazide Diuretics

FDA approved drugs -> Active ingredient

FDA approved drugs -> Active ingredient

225 °C

225 °C

The Approved Drug Products with Therapeutic Equivalence Evaluations List identifies currently marketed prescription drug products, incl methylclothiazide, approved on the basis of safety and effectiveness by FDA under sections 505 of the Federal Food, Drug, and Cosmetic Act.

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

Many diabetic patients regulated by chlorpropamide or other sulfonylureas exhibit impaired diabetic control when any thiazide diuretic is added to the drug regimen. ... This drug interaction may occur with acetohexamide, tolazamide, and tolbutamide. /thiazide diuretics/

Thiazides enhance the antihypertensive action of guanethidine, allowing the dose of guanethidine to be reduced and decr the incidence of adverse reactions. ... Bethanidine and debrisoquin are chemically and Pharmacologically related to guanethidine and may be expected to interact with hydrochlorothiazide. /thiazide diuretics/

Chlorothiazide and other thiazide diuretics enhance the cardiotoxic and neurotoxic effects of lithium and these drugs should not be administered concurrently. /thiazide diuretics/

C - Cardiovascular system

QC - Cardiovascular system

Methyclothiazide, a diuretic-antihypertensive agent, is a member of the benzothiadiazine (thiazide) class of drugs. Methyclothiazide has a per mg natriuretic activity approximately 100 times that of the prototype thiazide, chlorothiazide. At maximal therapeutic dosages, all thiazides are approximately equal in their diuretic/natriuretic effects. Like other benzothiadiazines, methyclothiazide also has antihypertensive properties, and may be used for this purpose either alone or to enhance the antihypertensive action of other drugs.

Methyclothiazide appears to block the active reabsorption of chloride and possibly sodium in the ascending loop of Henle, altering electrolyte transfer in the proximal tubule. This results in excretion of sodium, chloride, and water and, hence, diuresis. As a diuretic, methyclothiazide inhibits active chloride reabsorption at the early distal tubule via the Na-Cl cotransporter, resulting in an increase in the excretion of sodium, chloride, and water. Thiazides like methyclothiazide also inhibit sodium ion transport across the renal tubular epithelium through binding to the thiazide sensitive sodium-chloride transporter. This results in an increase in potassium excretion via the sodium-potassium exchange mechanism. The antihypertensive mechanism of methyclothiazide is less well understood although it may be mediated through its action on carbonic anhydrases in the smooth muscle or through its action on the large-conductance calcium-activated potassium (KCa) channel, also found in the smooth muscle.

Acute admin of thiazides increases the excretion of uric acid. However, uric acid excretion is reduced following chronic admin... . The acute effects of inhibitors of Na+-Cl- symport on Ca2+ excretion are variable; when admin chronically, thiazide diuretics decr Ca2+ excretion. The mechanism is unknown but may involve increased proximal reabsorption due to volume depletion as well as direct effects of thiazides to incr Ca2+ reabsorption in the /distal convoluted tubule/. Thiazide diuretics may cause a mild magnesuria by a poorly understood mechanism, and there is increasing awareness that long-term use of thiazide diuretics may cause magnesium deficiency, particularly in the elderly. /Thiazide diuretics/

Thiazides inhibit reabsorption of sodium and ...chloride in distal segment. ... As /a/ class...have important action on excretion of potassium that results from increased secretion of cation by distal tubule. ... Glomerular filtration rate may be reduced by thiazides, particularly with iv admin for exptl purposes. /thiazide diuretics/