Losartan Side Effects
Medically reviewed by Drugs.com. Last updated on Oct 26, 2023.
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.
Serious side effects of Losartan
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
Other side effects of Losartan
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]
Frequently asked questions
- Can you eat bananas when taking losartan?
- Does Losartan block the receptor used by the Coronavirus?
- Losartan vs Valsartan - What's the difference between them?
- Does losartan cause rapid heart rate, irregular heartbeat or low blood pressure?
- Are losartan and losartan potassium the same or different drugs?
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References
1. Product Information. Cozaar (losartan). Merck & Co., Inc. 2001;PROD.
2. Cerner Multum, Inc. UK Summary of Product Characteristics.
3. Cerner Multum, Inc. Australian Product Information.
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.