Skip to Content

Losartan Side Effects

In Summary

Commonly reported side effects of losartan include: asthenia, chest pain, diarrhea, fatigue, and hypoglycemia. Other side effects include: hyperkalemia, hypotension, and orthostatic hypotension. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to losartan: oral tablet

Warning

Oral route (Tablet)

When pregnancy is detected, discontinue losartan as soon as possible. Drugs that act directly on the renin-angiotensin system can cause injury or death to the developing fetus.

Side effects requiring immediate medical attention

Along with its needed effects, losartan may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking losartan:

Less common

  • Blurred vision
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • confusion
  • difficult breathing
  • dizziness
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • fainting
  • fast or irregular heartbeat
  • nausea or vomiting
  • nervousness
  • numbness or tingling in the hands, feet, or lips
  • stomach pain
  • sweating
  • unusual tiredness or weakness
  • weakness or heaviness of the legs

Incidence not known

  • Black, tarry stools
  • bleeding gums
  • blood in the urine or stools
  • coma
  • convulsions
  • cough
  • decreased urine output
  • difficulty swallowing
  • headache
  • hives, itching, skin rash
  • increased thirst
  • large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • muscle pain or cramps
  • pinpoint red spots on the skin
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • tightness in the chest
  • unusual bleeding or bruising

Side effects not requiring immediate medical attention

Some side effects of losartan may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

  • Body aches or pain
  • chills
  • continuing ringing or buzzing or other unexplained noise in the ears
  • decreased interest in sexual intercourse
  • difficulty having a bowel movement (stool)
  • ear congestion
  • feeling of constant movement of self or surroundings
  • feeling sad or empty
  • headache, severe and throbbing
  • hearing loss
  • inability to have or keep an erection
  • increased sensitivity of the skin to sunlight
  • irritability
  • lack of appetite
  • loss in sexual ability, desire, drive, or performance
  • loss of interest or pleasure
  • loss of voice
  • redness or other discoloration of the skin
  • sensation of spinning
  • severe sunburn
  • sneezing
  • sore throat
  • stuffy or runny nose
  • trouble concentrating
  • trouble sleeping

Incidence not known

  • Change or loss of taste
  • dark urine
  • general tiredness and weakness
  • light-colored stools
  • yellow eyes and skin

For Healthcare Professionals

Applies to losartan: oral tablet

General

The most common adverse reactions were upper respiratory infection and dizziness.[Ref]

Respiratory

Common (1% to 10%): Nasal congestion, upper respiratory infection, sinusitis, pharyngitis, cough, sinus disorder

Uncommon (0.1% to 1%): Dyspnea

Frequency not reported: Bronchitis, pharyngeal discomfort, epistaxis, rhinitis, respiratory congestion[Ref]

Gastrointestinal

Common (1% to 10%): Abdominal pain, nausea, diarrhea, dyspepsia

Uncommon (0.1% to 1%): Obstipation, vomiting

Frequency not reported: Constipation, dental pain, dry mouth, flatulence, gastritis[Ref]

Musculoskeletal

Common (1% to 10%): Muscle cramp, back pain, leg pain, myalgia

Frequency not reported: Arm pain, hip pain, joint swelling, knee pain, musculoskeletal pain, shoulder pain, stiffness, arthralgia, arthritis, fibromyalgia, muscle weakness

Postmarketing reports: Rhabdomyolysis[Ref]

Renal

Common (1% to 10%): Renal impairment, renal failure, BUN increased, serum creatinine increased[Ref]

Nervous system

Common (1% to 10%): Dizziness, headache, vertigo

Uncommon (0.1% to 1%): Somnolence

Rare (less than 0.1%): Paresthesia, syncope, cerebrovascular accident

Frequency not reported: Ataxia, hypesthesia, memory impairment, migraine, peripheral neuropathy, tremor, taste perversion, tinnitus[Ref]

Other

Common (1% to 10%): Asthenia/fatigue, edema/swelling, chest pain

Frequency not reported: Facial edema, fever, orthostatic effects

Postmarketing reports: Malaise[Ref]

Metabolic

Common (1% to 10%): Hyperkalemia, serum potassium increased, hypoglycemia

Frequency not reported: Anorexia, gout

Postmarketing reports: Hyponatremia[Ref]

Cardiovascular

Common (1% to 10%): Orthostatic hypotension

Uncommon (0.1% to 1%): Palpitation, angina pectoris

Rare (less than 0.1%): Atrial fibrillation

Frequency not reported: Second degree atrioventricular block, hypotension, myocardial infarction, sinus bradycardia, tachycardia, ventricular tachycardia, ventricular fibrillation, flushing

Postmarketing reports: Vasculitis[Ref]

Psychiatric

Common (1% to 10%): Insomnia

Uncommon (0.1% to 1%): Sleep disorder

Frequency not reported: Anxiety, anxiety disorder, confusion, depression, dream abnormality, libido decreased, nervousness, panic disorder[Ref]

Hematologic

Common (1% to 10%): Anemia

Rare (less than 0.1%): Hemolysis

Postmarketing reports: Thrombocytopenia, hemoglobin decreased, hematocrit decreased[Ref]

Dermatologic

Uncommon (0.1% to 1%): Urticaria, pruritus, rash

Rare (less than 0.1%): Angioedema, superficial peeling of palms

Frequency not reported: Alopecia, dermatitis, dry skin, ecchymosis, erythema, photosensitivity, sweating

Postmarketing reports: Erythroderma[Ref]

Hepatic

Rare (less than 0.1%): ALT increased

Postmarketing reports: Hepatitis, liver enzymes increased, serum bilirubin increased, pancreatitis, liver function abnormalities[Ref]

Genitourinary

Frequency not reported: Impotence, nocturia, urinary frequency, urinary tract infection[Ref]

Ocular

Frequency not reported: Blurred vision, burning/stinging in the eye, conjunctivitis, visual acuity decreased[Ref]

Immunologic

Frequency not reported: Flu-like symptoms

Postmarketing reports: Anaphylactic reactions, hypersensitivity reactions[Ref]

References

1. Cerner Multum, Inc. "Australian Product Information." O 0

2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

3. "Product Information. Cozaar (losartan)." Merck & Co, Inc, West Point, PA.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

Related questions