2. Why are there potassium-sparing
diuretics?
Sometimes when you take a diuretic, you lose too
much potassium from your body along with the
extra water you pass. This can make your
potassium levels low, which can be quite
dangerous. The potassium-sparing diuretics help
to stop this happening. They can be used on their
own but are most commonly used in combination
with another type of diuretic. This is because
they are not so strong as loop diuretics and
thiazide diuretics.
3. There are four potassium-sparing diuretics.
Amiloride
Amiloride belongs to the group of medicines known as potassium-sparing
diuretics. A diuretic is a medicine which increases the amount of urine
that you pass out from your kidneys. They are often referred to as 'water'
tablets.
Amiloride is a 'water' tablet (diuretic).
It will make you go to the toilet more often to pass urine.
Any side-effects are usually mild.
4. Triamterene
Triamterene belongs to the group of medicines
known as potassium-sparing diuretics. A diuretic is
a medicine which increases the amount of urine
that you pass out from your kidneys.
Triamterene is a 'water' tablet (diuretic) - it will make
you want to go to the toilet more often to pass urine.
It may cause your urine to look slightly blue in some
lights - this is harmless.
Any side-effects are usually mild.
5. Eplerenone
Heart failure means that your heart is not functioning as
well as it should. In a healthy heart, a set amount of
blood enters the heart during each heartbeat and is
pumped out again. If you have heart failure, your heart
cannot cope with pumping the full amount of blood in
each heartbeat.
Take eplerenone tablets once a day.
Do not use salt substitutes while you are taking
eplerenone.
Make sure your doctor knows about any other medicines
you are taking alongside eplerenone.
6. Spironolactone
Spironolactone is used to treat fluid
retention (oedema) caused by liver
disease, kidney problems or heart
failure. Oedema occurs when fluid leaks
out of your blood vessels, causing
swelling in the tissues of your lungs, feet
or ankles.
Spironolactone is a diuretic, also known
as a 'water tablet'.
It will make you go to the toilet more often
to pass urine.
The most common side-effect is a mild
stomach upset. This is not usually
troublesome.
7. What are the main uses of potassium-
sparing diuretics?
To prevent low levels of potassium (hypokalaemia)
occurring when other diuretics are used (prescribed in
combination with the other diuretic).
In the treatment of heart failure. In this condition, fluid
accumulates in your body, due to the heart not pumping
blood around the body as well as it normally would. So, you
may become breathless (as fluid accumulates in the lungs).
Your ankles and legs may swell with extra fluid in the
tissues (oedema). Other causes of oedema can also be
helped by diuretics.
In helping to reduce a condition called ascites where fluid
builds up inside the tummy (abdominal) cavity. This can
happen due to various conditions such as cirrhosis of the
liver and certain kinds of cancer.
8. How do potassium-sparing diuretics work?
Amiloride and triamterene work by making the kidneys pass out more fluid.
They do this by interfering with the transport of salt and water across certain
cells in the kidneys. As more fluid is passed out by the kidneys, less fluid
remains in the bloodstream.
Eplerenone and spironolactone work in a slightly different way to amiloride
and triamterene. These medicines block the action of a hormone called
aldosterone and this causes the kidney to pass out more fluid and keep
potassium. This is why they are sometimes referred to as aldosterone
antagonists.
9. Low potassium (hypokalemia) has many causes.
The most common cause is excessive potassium
loss in urine due to prescription medications that
increase urination. Also known as water pills or
diuretics, these types of medications are often
prescribed for people who have high blood
pressure or heart disease.
10. WHAT ARE OSMOTIC DIURETICS AND HOW
DO THEY WORK?
Osmotic diuretics are a class of drugs that
increase the production of urine people with
sudden kidney problems. Osmotic diuretics
produce diuresis by increasing the osmotic
pressure within the kidney.
11. DRUG NAME OF OSMOTIC DIURETICS
Mannitol
Mannitol is a diuretic used to force urine
production in people with acute (sudden) kidney
failure. Mannitol injection is also used to reduce
swelling and pressure inside the eye or around the
brain.
12. There are three types of IV fluids:
1. Isotonic
2. Hypotonic
3. Hypertonic
13. Isotonic IV fluids
Isotonic IV fluids are used to increase fluid volume
due to blood loss, surgery, or dehydration.
There are many different types of common
isotonic fluids, such as: 1. Normal Saline (0.9%
NaCl, NS) 2. 5% Dextrose in Water (D5W) 3.
Lactated Ringer’s Solution (LR)
14. Hypotonic IV fluids
Hypotonic IV fluids are designed to bring fluid from
the bloodstream into the cells and tissues to help in
body waste excretion. In other words, they are
commonly used to help patients avoid dehydration.
There are many common types of hypotonic fluid,
such as:
– 0.45% Normal Saline (Half Normal Saline)
– 0.225% Normal Saline (Quarter Normal Saline)
– 2.5% Dextrose
15. Hypertonic IV Fluids
Hypertonic IV fluids are used to shift fluids into the
bloodstream to dilute electrolytes. Some of these
fluids often appear on the list of vesicants. More on
those in a moment.
Saline Solutions: >0.9%
a. 3% NaCl
b. 5% NaCl
2. Dextrose Solutions >=10%
a. D10W
b. D20W
c. D50W
3. Dextrose 5% in 0.9 Normal Saline (N5NS)
4. Dextrose 5% in 0.45% Normal Saline (D5 1/2 NS)
5. Dextrose 5% in Lactated Ringer’s (D5LR)
16. What are electrolytes?
Electrolytes are substances that have a natural positive or
negative electrical charge when dissolved in water. An
adult's body is about 60% water, which means nearly every
fluid and cell in your body contains electrolytes. They
help your body regulate chemical reactions, maintain the
balance between fluids inside and outside your cells, and
more.
Hyper-: A condition that starts with “hyper” means it
involves too much of something.
Hypo-: A condition that starts with “hypo” means it
involves too little of something.
Ion: An atom that has an electrical charge.
17. Sodium (+)
Sodium plays a critical role in helping your cells
maintain the right balance of fluid. It’s also used to
help cells absorb nutrients. It’s the most abundant
electrolyte ion found in the body.
Hypernatremia (too much sodium): Can cause confusion
or behavior changes, unusually strong reflexes and loss
of muscle control, seizures and coma.
Hyponatremia (not enough sodium): Confusion,
irritability, weakened reflexes, nausea and vomiting,
seizures and coma.
18. Magnesium (+)
Magnesium helps your cells as they turn nutrients
into energy. Your brain and muscles rely heavily on
magnesium to do their job.
Hypermagnesemia (too much magnesium): Heart
rhythm changes and arrhythmias, weakened
reflexes, decreased ability to breathe and cardiac
arrest (your heart stops).
Hypomagnesemia (not enough magnesium):
Muscle weakness, twitching and loss of control,
heart arrhythmias. This commonly happens in
connection with calcium and potassium
deficiencies.
19. Potassium chloride
Potassium chloride is irritating to the
gastrointestinal tract, even to the extent of
causing perforation. In a retrospective study at
surgical clinics in Stockholm County there were
cases of small-bowel ulceration in which a
connection with slow-release potassium chloride
tablets was probable. Most of the ulcers had
caused stenosis of 1–2 cm of gut, and in four cases
there was also perforation of the bowel wall.
