hydrochlorothiazide

Hydrochlorothiazide
Systematic (IUPAC) name
6-chloro-1,1-dioxo-3,4-dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide
Identifiers
CAS number	58-93-5
ATC code	C03AA03
PubChem	3639
ChemSpider	3513
Chemical data
Formula	C7H8ClN3O4S2
Mol. mass	297.74
SMILES	eMolecules & PubChem
Pharmacokinetic data
Bioavailability	Variably absorbed from GI tract
Metabolism	does not undergo significant metabolism (>95% excreted unchanged in urine)[1]
Half life	5.6-14.8 hours
Excretion	Primarily excreted unchanged in urine
Therapeutic considerations
Pregnancy cat.	B (D if used to treat pregnancy-induced hypertension)
Legal status	℞ Prescription only
Routes	Oral (capsules, tablets, oral solution)

Hydrochlorothiazide, abbreviated HCTZ, HCT, or HZT, is a first line diuretic drug of the thiazide class that acts by inhibiting the kidneys' ability to retain water. This reduces the volume of the blood, decreasing blood return to the heart and thus cardiac output and, by other mechanisms, is believed to lower peripheral vascular resistance. Hydrochlorothiazide is sold both as a generic drug and under a large number of brand names, including Apo-Hydro, Aquazide H, Dichlotride, Hydrodiuril, HydroSaluric, Microzide, Esidrex, and Oretic.

Mechanism of action

Hydrochlorothiazide belongs to the thiazide class of diuretics, acting on the kidneys to reduce sodium (Na) reabsorption in the distal convoluted tubule. This increases the osmolarity in the lumen, causing less water to be reabsorbed by the collecting ducts. This leads to increased urinary output.

Indications

HCTZ is often used in the treatment of hypertension, congestive heart failure, symptomatic edema and the prevention of kidney stones. It is effective for nephrogenic diabetes insipidus and is also sometimes used for hypercalciuria, Dent's disease and Meniere's disease.

Hypokalemia, an occasional side effect, can be usually prevented by potassium supplements or by combining hydrochlorothiazide with a potassium-sparing diuretic.

Thiazides are also used in the treatment of osteoporosis. Thiazides decrease mineral bone loss by promoting calcium retention in the kidney, and by directly stimulating osteoblast differentiation and bone mineral formation.^[2]

Side effects

• Hypokalemia
• Hypomagnesemia
• Hyperuricemia and gout
• High blood sugar
• Hyperlipidemia
• Hypercalcemia
• Headache
• Nausea/vomiting
• Photosensitivity

See also

• Benicar HCT
• Diovan HCT

External links

• NIH medlineplus druginfo

References