Hygroton

Country: Australia

Language: English

Source: Department of Health (Therapeutic Goods Administration)

Active ingredient:

Chlorthalidone

Patient Information leaflet

HYGROTON

_chlorthalidone_
_____________________________________________________________________________________
CONSUMER MEDICINE INFORMATION
WHAT IS IN THIS LEAFLET
This leaflet answers some common 
questions about Hygroton.
It does not contain all the available 
information. It does not take the 
place of talking to your doctor or 
pharmacist.
The information in this leaflet was 
last updated on the date listed on the 
final page. Some more recent 
information on the medicine may be 
available.
YOU SHOULD ENSURE THAT YOU SPEAK 
TO YOUR PHARMACIST OR DOCTOR TO 
OBTAIN THE MOST UP TO DATE 
INFORMATION ON THE MEDICINE. 
Those updates may contain important 
information about the medicine and 
its use of which you should be aware. 
All medicines have risks and benefits.
Your doctor has weighed the risks of 
you taking this medicine against the 
benefits they expect it will provide.
IF YOU HAVE ANY CONCERNS ABOUT THIS
MEDICINE, ASK YOUR DOCTOR OR 
PHARMACIST.
KEEP THIS LEAFLET WITH THE MEDICINE.
You may need to read it again.
WHAT HYGROTON IS USED 
FOR
Hygroton is used to treat high blood 
pressure (also called hypertension) 
and fluid build-up. 
Everyone has blood pressure. This 
pressure helps to move your blood 
around your body. Your blood
pressure may be different at various 
times of the day, depending on how 
busy you are. 
You have high blood pressure 
(hypertension) when your blood 
pressure stays higher than is needed, 
even when you are calm and relaxed.
There are usually no symptoms of 
high blood pressure. The only way of 
knowing that you have it is to have 
your blood pressure checked on a 
regular basis. You may feel fine and 
have no symptoms but, if high blood 
pressure is not treated, it can lead to 
serious health problems. Hygroton 
helps to lower your blood pressure.
Hygroton is also used to treat fluid 
build-up caused by heart or liver 
problems. Hygroton belongs to a 
group of medicines called diuretics 
(commonly called

Summary of Product characteristics

PRODUCT INFORMATION
HYGROTON®
(CHLORTHALIDONE TABLETS 25 MG)
NAME OF THE MEDICINE
Chlorthalidone
2-chloro-5-(1-hydroxy-3-oxo-1,2-dihydroisoindol-1-yl)- benzenesulfonamide
Molecular weight - 338.767
CAS number - 77-36-1
DESCRIPTION
Chlorthalidone is a white or creamy-white odourless, or almost
odourless, tasteless crystalline 
powder.  Melting point about 220°C with decomposition.
 Practically insoluble in water; 
soluble 1 in 150 of alcohol, 1 in 650 of chloroform, and 1 in 25 of
methyl alcohol; slightly 
soluble in ether; soluble in solutions of alkali hydroxides.
Excipients: silica colloidal - anhydrous, lactose, magnesium
stearate, starch - maize, 
talc - purified, iron oxide yellow CI77492 and  iron oxide red
CI77491.
PHARMACOLOGY
PHARMACODYNAMICS
Chlorthalidone, the active substance of Hygroton, is a
benzothiadiazine (thiazide)-related 
diuretic with a long duration of action.
Thiazide and thiazide-like diuretics act primarily on the distal
renal tubule (early convoluted 
part), inhibiting NaCl reabsorption (by antagonising
the Na+ -Cl- cotransporter), and 
promoting Ca++ reabsorption (by an unknown mechanism). The enhanced
delivery of Na+  
and water to the cortical collecting tubule and/or the increased flow
rate leads to increased 
secretion and excretion of K+ and H+.
In persons with normal renal function, diuresis is induced after the
 administration of as little 
as 12.5 mg Hygroton. The resulting increase in urinary excretion of
sodium and chloride and 
the less prominent increase in urinary potassium are dose dependent
and occur both in normal 
and in oedematous patients. The diuretic effect sets in after 2 to 3
hours, reaches its maximum 
after 4 to 24 hours and may persist for 2 to 3 days.
Thiazide-induced diuresis initially leads to decreases in plasma
volume, cardiac output and 
systemic blood pressure. The renin-angiotensin-aldosterone system
may possibly become 
activated, blunting antihypertensive efficacy.
In hypertensive individuals, chlorthali