Cozaar

Generic name: losartan
Drug class: Angiotensin receptor blockers

Medically reviewed by A Ras MD.

What is Cozaar?

Cozaar is a prescription medicine called an angiotensin receptor blocker (ARB). It is used alone or with other blood pressure medicines to lower high blood pressure (hypertension), to lower the chance of stroke in patients with high blood pressure and a heart problem called left ventricular hypertrophy. Cozaar may not help Black patients with this problem, to slow the worsening of diabetic kidney disease (nephropathy) in patients with type 2 diabetes who have or had high blood pressure.

Cozaar has not been studied in children less than 6 years old or in children with certain kidney problems.

Description

COZAAR (losartan potassium) is an angiotensin II receptor blocker acting on the AT1 receptor subtype. Losartan potassium, a non-peptide molecule, is chemically described as 2-butyl-4-chloro-1-[p-(o-1H-tetrazol-5-ylphenyl)benzyl]imidazole-5-methanol monopotassium salt.

Its empirical formula is C22H22ClKN6O, and its structural formula is:

Losartan potassium is a white to off-white free-flowing crystalline powder with a molecular weight of 461.01. It is freely soluble in water, soluble in alcohols, and slightly soluble in common organic solvents, such as acetonitrile and methyl ethyl ketone. Oxidation of the 5-hydroxymethyl group on the imidazole ring results in the active metabolite of losartan.

COZAAR is available as tablets for oral administration containing either 25 mg, 50 mg or 100 mg of losartan potassium and the following inactive ingredients: microcrystalline cellulose, lactose hydrous, pregelatinized starch, magnesium stearate, hydroxypropyl cellulose, hypromellose, and titanium dioxide.

COZAAR 25 mg, 50 mg and 100 mg tablets contain potassium in the following amounts: 2.12 mg (0.054 mEq), 4.24 mg (0.108 mEq) and 8.48 mg (0.216 mEq), respectively. COZAAR 25 mg, COZAAR 50 mg, and COZAAR 100 mg may also contain carnauba wax.

Mechanism of Action

Angiotensin II [formed from angiotensin I in a reaction catalyzed by angiotensin converting enzyme (ACE, kininase II)] is a potent vasoconstrictor, the primary vasoactive hormone of the renin-angiotensin system, and an important component in the pathophysiology of hypertension. It also stimulates aldosterone secretion by the adrenal cortex. Losartan and its principal active metabolite block the vasoconstrictor and aldosterone-secreting effects of angiotensin II by selectively blocking the binding of angiotensin II to the AT1 receptor found in many tissues, (e.g., vascular smooth muscle, adrenal gland).

There is also an AT2 receptor found in many tissues but it is not known to be associated with cardiovascular homeostasis. Neither losartan nor its principal active metabolite exhibits any partial agonist activity at the AT1 receptor, and both have much greater affinity (about 1000-fold) for the AT1 receptor than for the AT2 receptor. In vitro binding studies indicate that losartan is a reversible, competitive inhibitor of the AT1 receptor. The active metabolite is 10 to 40 times more potent by weight than losartan and appears to be a reversible, non-competitive inhibitor of the AT1 receptor.

Neither losartan nor its active metabolite inhibits ACE (kininase II, the enzyme that converts angiotensin I to angiotensin II and degrades bradykinin), nor do they bind to or block other hormone receptors or ion channels known to be important in cardiovascular regulation.

What is the most important information I should know about Cozaar?

Cozaar can cause harm or death to an unborn baby.
Talk to your doctor about other ways to lower your blood pressure if you plan to become pregnant.
If you get pregnant while taking Cozaar, tell your doctor right away.

Who should not take Cozaar?

Do not take Cozaar if you are allergic to any of the ingredients in Cozaar. See the end of this guide for a complete list of ingredients in Cozaar.
Do not take Cozaar if you have diabetes and are taking a medicine called aliskiren to reduce blood pressure.

What should I tell my healthcare provider before taking Cozaar?

Tell your doctor about all of your medical conditions including if you:

are pregnant or planning to become pregnant. See “What is the most important information I should know about Cozaar?” above.
are breastfeeding. It is not known if Cozaar passes into your breast milk. You should choose either to take Cozaar or breastfeed, but not both.
are vomiting a lot or having a lot of diarrhea
have liver problems
have kidney problems

Tell your doctor about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Cozaar and certain other medicines may interact with each other.

Especially tell your doctor if you are taking:

potassium supplements
salt substitutes containing potassium
other medicines that may increase serum potassium
water pills (diuretics)
lithium (a medicine used to treat a certain kind of depression)
medicines used to treat pain and arthritis, called non-steroidal anti-inflammatory drugs (NSAIDs), including COX-2 inhibitors
other medicines to reduce blood pressure

How should I take Cozaar?

Take Cozaar exactly as prescribed by your doctor. Your doctor may change your dose if needed.
Cozaar can be taken with or without food.
If you miss a dose, take it as soon as you remember. If it is close to your next dose, do not take the missed dose. Just take the next dose at your regular time.
If you take too much Cozaar, call your doctor or Poison Control Center, or go to the nearest hospital emergency room right away.

What are the possible side effects of Cozaar?

Cozaar may cause the following side effects that may be serious:

Injury or death of unborn babies. See “What is the most important information i should know about Cozaar?” above.
Allergic reaction. Symptoms of an allergic reaction are swelling of the face, lips, throat or tongue. Get emergency medical help right away and stop taking Cozaar.
Low blood pressure (hypotension). Low blood pressure may cause you to feel faint or dizzy. Lie down if you feel faint or dizzy. Call your doctor right away.
For people who already have kidney problems, you may see a worsening in how well your kidneys work. Call your doctor if you get swelling in your feet, ankles, or hands, or unexplained weight gain.
High blood levels of potassium

The most common side effects of Cozaar in people with high blood pressure are:

“colds” (upper respiratory infection)
dizziness
stuffy nose
back pain

The most common side effects of Cozaar in people with type 2 diabetes with diabetic kidney disease are:

diarrhea
tiredness
low blood sugar
chest pain
high blood potassium
low blood pressure

Tell your doctor if you get any side effect that bothers you or that won’t go away.

This is not a complete list of side effects. For a complete list, ask your doctor or pharmacist.

General information about the safe and effective use of Cozaar

Medicines are sometimes prescribed for conditions that are not mentioned in patient information leaflets. Do not use Cozaar for a condition for which it was not prescribed. Do not give Cozaar to other people, even if they have the same symptoms that you have. It may harm them.

This guide summarizes the most important information about Cozaar. If you would like more information, talk with your doctor. You can ask your pharmacist or doctor for information about Cozaar that is written for health professionals.

How should I store Cozaar?

Store Cozaar tablets at 59°F to 86°F (15°C to 30°C).
Keep Cozaar in a tightly closed container that protects the medicine from light.
Keep Cozaar and all medicines out of the reach of children.

What are the ingredients in Cozaar?

Active ingredients: losartan potassium

Inactive ingredients: microcrystalline cellulose, lactose hydrous, pregelatinized starch, magnesium stearate, hydroxypropyl cellulose, hypromellose, and titanium dioxide. Cozaar 25 mg, Cozaar 50 mg, and Cozaar

100 mg may also contain carnauba wax.

Label

PRINCIPAL DISPLAY PANEL – 25 MG TABLET BOTTLE LABEL

NDC 78206-121-01
Cozaar®
(Losartan Potassium
Tablets)
25 mg
Each tablet contains 25 mg of losartan potassium.
Store at 25°C (77°F); excursions permitted to 15-30°C
(59-86°F) [see USP Controlled Room Temperature].
Keep container tightly closed.
Protect from light.
Rx only
90 Tablets

PRINCIPAL DISPLAY PANEL – 50 MG TABLET BOTTLE LABEL

NDC 78206-122-01
Cozaar®
(Losartan Potassium
Tablets)
50 mg
Each tablet contains 50 mg of losartan potassium.
Store at 25°C (77°F); excursions permitted to 15-30°C
(59-86°F) [see USP Controlled Room Temperature].
Keep container tightly closed.
Protect from light.
Rx only
30 Tablets

PRINCIPAL DISPLAY PANEL – 100 MG TABLET BOTTLE LABEL

NDC 78206-123-01
Cozaar®
(Losartan Potassium
Tablets)
100 mg
Each tablet contains 100 mg of losartan potassium.
Store at 25°C (77°F); excursions permitted to 15-30°C
(59-86°F) [see USP Controlled Room Temperature].
Keep container tightly closed.
Protect from light.
Rx only
30 Tablets