Compare Losartan vs. hydrochlorothiazide

Head-to-head comparisons of medication uses, side effects, ratings, and more.

Cozaar
(losartan)

Microzide
(hydrochlorothiazide )

Lowers blood pressure. Cozaar (Losartan) is a good blood pressure-lowering medicine that protects kidney function like an ACE inhibitor, but with fewer side effects.Removes water from the body, which lowers blood pressure. Microzide (hydrochlorothiazide (HCTZ)) is a well-tolerated water pill that's often the first-choice treatment for mild high blood pressure.
Reviews & ratings
Filter group. All currently selected
Filter group. All currently selected
4.99Losartan
Reviews for Losartan
57%
of people (All ages) say Losartan is worth it
48%
say it works well
16%
say it's a big hassle
535 reviews
Have you used Cozaar (losartan)?
Worth itNot sureNot worth it
Reviews for hydrochlorothiazide
47%
+10% better vs. Losartan
31%
+17% better vs. Losartan
16%
Same vs. Losartan
139 reviews
Have you used Microzide (hydrochlorothiazide )?
Worth itNot sureNot worth it
Side effects
Losartanhydrochlorothiazide
  • Upper respiratory infection 1%
  • Dizziness 1%
  • Back pain 1%
  • Nasal congestion 1%
  • Urinary tract infection 6%
  • Diarrhea 5%
  • Muscle weakness/fatiguea/fatigue 4%
  • Low red blood cells 3%
  • Low blood sugar 4%
  • Back pain 2%
More Losartan side effects »

The hydrochlorothiazide FDA package insert doesn’t have numbers about how common side effects are.

More about hydrochlorothiazide side effects »
How it works
Losartanhydrochlorothiazide
Cozaar (Losartan) is an angiotensin receptor blocker (ARB). It blocks a chemical that tightens blood vessels. This makes blood vessels relax, which lowers blood pressure and allows more blood and oxygen to get to your heart and other organs.Microzide (hydrochlorothiazide (HCTZ)) is a thiazide diuretic (water pill) that makes you urinate more. It works in the kidneys to remove extra water and certain electrolytes, while lowering blood pressure and reducing swelling.
Type of medication
Losartanhydrochlorothiazide
Prescription onlyPrescription only
Available as
Losartanhydrochlorothiazide
  • Pill
  • Pill
Used for
Losartanhydrochlorothiazide
Risk factors for serious side effects
Losartanhydrochlorothiazide
  • Women of childbearing age
  • Concurrent liver disease
  • Current kidney problems
  • Medicine that increase potassium
  • Use of salt substitute
Detailed Cozaar (losartan) risks & warnings »
  • Current electrolyte imbalance
  • Lower kidney function
  • Dehydration
  • History of sulfa allergies
  • History of gout
Detailed Microzide (hydrochlorothiazide ) risks & warnings »
Pregnancy

Research studies with real people found harmful effects on unborn babies, but the benefits might outweigh the risks even if you’re pregnant. Talk with your doctor.

Research studies with animals haven’t found a risk to unborn babies, but it hasn’t been properly studied in humans.

Kidneys and liver
Losartanhydrochlorothiazide
  • Requires routine blood tests to check kidney function.
  • Protects kidney function, which is especially useful for people with diabetes or mild-to-moderate kidney disease.
  • Requires routine blood tests to check kidney function.
Upsides and benefits
Losartanhydrochlorothiazide
  • A first-choice blood pressure treatment for many people.
  • Lowers the risk of heart attack and stroke.
  • Similar to ACE inhibitors (like Lisinopril), with fewer side effects like cough and swelling.
  • Protects kidney function, which is especially useful for people with diabetes or mild-to-moderate kidney disease.
  • Recommended for anyone with heart failure since it lowers the risk of death and further damage to your heart.
  • Does a good job getting rid of extra fluids in your body by making you urinate more.
  • A first-choice blood pressure treatment. Works especially well for people of African descent.
  • Lowers the risk of heart attack and stroke.
  • Good option if you have high blood pressure and heart failure.
  • Most people have very few side effects from Microzide (hydrochlorothiazide (HCTZ)).
  • Can be good for patients with osteoporosis since it raises the body's level of calcium.
Downsides and risks
Losartanhydrochlorothiazide
  • Requires a yearly blood test to see how the medicine is affecting your body.
  • Not safe to use if you're pregnant.
  • Makes you urinate more often.
  • Microzide (hydrochlorothiazide (HCTZ)) doesn't work well in people with severe kidney problems.
  • It can increase the risk of gout attacks in people with poor kidney function or a history of gout.
  • People with a sulfa allergy may be allergic to Microzide (hydrochlorothiazide (HCTZ)).
Tips from our pharmacists for people taking the medication
Losartanhydrochlorothiazide
  • Can cause dizziness in the first few days.
  • Check your blood pressure 1 week after starting this medicine, and tell your doctor if it hasn't improved.
  • Tell your doctor about any dizziness, fatigue, cough, or throat irritation that doesn't go away.
  • Requires routine blood tests to check kidney function.
  • Don't take it if you're pregnant.
  • Microzide (hydrochlorothiazide (HCTZ)) starts working in about 2 hours.
  • It makes you urinate more often, so don't take it at bedtime.
  • Can cause dizziness in the first few days.
  • Check your blood pressure 1 week after starting this medicine, and tell your doctor if it hasn't improved.
  • Tell your doctor about any tiredness or muscle weakness that doesn't go away.
  • Requires routine blood tests to check kidney function.
Learn more
More about LosartanSide effectsReviews & ratingsAlternativesFDA package insert
Have you used Cozaar (losartan)?
Worth itNot sureNot worth it
More about hydrochlorothiazideSide effectsReviews & ratingsAlternativesFDA package insert
Have you used Microzide (hydrochlorothiazide )?
Worth itNot sureNot worth it