Drug Class
Carbonic Anhydrase Inhibitors
Drug Names
acetazolamide, methazolamide
MOA
Increase sodium excretion by decreasing sodiumhydrogen ion exchange throughout the renal tubule.
Bicarbonate ions in the tubule increase osmotic pressure
and results in osmotic diuresis. Sulphonamide based.
Indications
Mainly used to treat glaucoma, edema
(secondary to heart failure), epilepsy
(anticonvulsant), high-altitude sickness.
Contraindications
Allergy to sulphonamides,
hepatic disease, hypokalemia,
hyponatremia, metabolic
acidosis.
Adverse Effects
Drug Interactions
Rash, anaphylaxsis, Stevens-Johnson Topical CAIs:
syndrome (due to allgeric reaction to None
sulphonamides), abdominal pain,
Oral acetazolamide:
diarrhea, nausea, vomiting, blurred Aspirin. Consider using
vision, headach, tinnitus,
ibuprofen.
paresthesia.
Loop Diuretics
bumetanide, ethacrynic acid, furosemide
Inhibit resorption of sodium and chloride in the thick
Diuretic of choice when rapid effects are
Severe electrolyte imbalances
ascending limb of the loop of Henle. Activates renal
required, good efficacy with elderly patients, (loss), hepatic coma,
prostaglandins resulting in dialation of blood vessels in the effective in patients with seriously impaired nephrotoxic meds.
kidney and elsewhere.
GFR (creatinine clearance < 30 mL/min).
Treatment of edema associated with:
- Heart Failure
- Liver disease
- Renal diseases
- Pulmonary edema
- Ascites
Osmotic Diuretics
mannitol (Osmitrol) - osmotic diuretic of
choice
Increases the osmotic pressure of glomerular filtrate, thus Cerebral edema, intracranial pressure, early
decreasing water and electrolytes reabsorption while
phase of AKI, glaucoma (intraocular
increasing sodium, chloride, potassium, calcium,
pressure), urinary excretion of toxic
phosphorous, uric acid, urea, magnesium in urinary
substances (lithium, salicylates, barbituates,
output. Prevents kidney damage in ARF.
bromides).
Drug allergy, hyperkalemia
CNS:
None
(serum K+ > 5.5 mmol/L),
Convulsions, headache, blurred
severe kidney failure or anuria. vision
Triamterene use in patients
CV:
with liver failure.
Thrombophlebitis, pulmonary
congestion, chest pain, tachycardia
Other:
Chills, fever
Potassium-Sparing Diuretics
amiloride hydrochloride (Midamor),
eplerenone (Inspar), spironolactone
(Aldactone), triamterene (available only in
combination with hydrochlorothiazide)
Interfere with sodium resorption at the distal tubule, thus Hyperaldosteronism (spironolactone - key
decreasing potassium excretion. Not a potent diuretic.
drug for pediatric cardiac patients),
hypertension, edema, ascites, heart failure,
adjunct to other diuretics (offsets loss of
potassium).
Drug allergy, severe kidney
disease, pulomary edema,
active intracranial bleeding
(hematological stroke).
CNS:
Dizziness, headache, blurred vision,
tinnitus, ototoxicity
CV:
Dehydration/hypervolemia
GI:
Nausea, vomiting, diarrhea
Hematological:
Agranulocytosis, thrombocytopenia,
neutropenia
Metabolic:
Hypokalemia, hyperglycemia,
hyperuricemia, hyponatremia,
hypochloremia, hypocalcemia,
hypomagnesemia, metabolic
acidosis in severe cases.
CNS:
Dizziness, headache
GU:
Urinary incontinence
GI:
Cramps, nausea, vomiting, diarrhea
Metabolic:
Hyperkalemia (diabetes
mellitus, renal impairment)
Aminoglycosides,
vancomycin,
corticosteroids, digoxin,
lithium, NSAIDs
Hyperkalemia when
given with potassium
supplements or ACE
Inhibitors (captopril,
enalapril, ramipril).
Spironolactone and
digoxin used
concurrently can
increase the risk of
digoxin toxicity leading
to fatal arrythmias.
Spironolatone specific:
GU:
gynecomastia, amenorrhea, irregular
menses, postmenopausal bleeding
Lithium combined with
potassium-sparing
Triamterene specific:
diuretics can result in
GU:
lithium toxicity.
Formation of kidney stones and
urinary casts.
Metabolic:
Reduction of folic acid
Thiazides and Thiazide-Like
Diuretics
chlorthalidone, hydrochlorothiazide (Urozide), Increase excretion of water and sodium by inhibiting
indapamide, metolazone
resorption in the early distal convoluted tubule.
Chemically related to sulphonomides. Cause excretion of
the following in urine:
- Water
- sodium
- potassium
- magnesium
- chloride
May increase serum level of calcium, glucose, uric acid.
Often first-line agent in treatment of
hypertension . Long-term management of:
- CHF
- hypertension
- hepatic cirrhosis
- renal dysfunction (not stage 1 Acute Renal
Failure )
Pregnancy, allergy to
sulphonomides, cases where
rapid diuresis is required.
CNS:
Glycosides (digoxin),
Dizziness, headache, blurred vision corticosteroids, NSAIDs,
GU:
lithium, oral
Erectile dysfunction
antihyperglycemics.
GI:
NB: Cholestyramine
Anorexia, nausea, vomiting, diarrhea (Questran) will
Hematological:
reduce absorption of
Agranulocytosis, jaundice,
thiazides and should
leukopenia
not be given
Metabolic:
together.
Hypokalemia, hyperglycemia,
hyperuricemia, glycosuria,
hypochloremia alkalosis
(metabolic alkalosis)