Are you taking losartan to manage your high blood pressure or protect your kidneys? While losartan is a trusted medication, it can sometimes cause side effects that may disrupt you. You might feel dizzy, get headaches, or experience fatigue, making it harder to stay active and focused. These side effects can be frustrating and even worrying, causing you to question if losartan is right for you.
In this article, you will discover how you can manage the side effects of losartan, helping you continue your treatment with confidence and ease.
🔑 Key Takeaways ➤ Headaches are common, but they might not be caused by losartan. If they bother you, talk to your doctor. ➤ Feeling tired is normal at first. Try exercising regularly to boost your energy. ➤ If you have stomach pain or feel very sick, stop taking losartan and see your doctor right away. ➤ Losartan can raise your potassium levels. Watch your diet and get your blood tested regularly. ➤ Rarely, you might experience severe swelling in your face or throat. Seek emergency help immediately if this happens. ➤ Drink plenty of fluids if you have diarrhea while on losartan to stay hydrated. ➤ You may become more sensitive to sunlight. Use sunscreen and wear protective clothing when outside. |
Common Side Effects of Losartan and How to Manage Them
Losartan is a widely used medication for treating high blood pressure, diabetic kidney disease, and other health conditions. While it helps many people, some may experience side effects. These side effects occur in more than 1 out of every 100 people.
Let’s dive into these side effects and how you can handle them effectively.
Dizziness
Dizziness is a common side effect of losartan, reported in about 4.1% of patients during clinical trials. In comparison, only 2.4% of those given a placebo experienced dizziness. This usually happens as your body adjusts to the medication.
However, dizziness can be more noticeable if you’re dehydrated, taking a high dose, or have other health conditions.
When you feel dizzy, try standing up slowly from a sitting or lying position. If dizziness strikes, sit or lie down until it passes. It’s best to avoid driving, biking, or operating machinery when you’re feeling dizzy.
Headaches
Headaches affect around 14.1% of people taking losartan. Interestingly, 17.2% of those taking a placebo also reported headaches. This suggests that headaches might not be directly caused by losartan itself.
To manage headaches, you can use over-the-counter pain relievers like acetaminophen. However, always check with your doctor first to ensure it’s safe for you. Compared to other blood pressure medications, losartan doesn’t cause more headaches.
Nausea
Nausea is a common side effect with many medications, but is less common with losartan. In fact, a previous study showed nausea to be less common with losartan than placebo. In two of the dosing groups, losartan 50 mg and losartan 150 mg, no patients reported nausea, compared to 6% of those taking a placebo.
To ease nausea if it develops, try eating smaller meals more frequently and avoid heavy, rich, or spicy foods.
Diarrhea
Diarrhea is another potential side effect of losartan. While it’s usually mild, some cases can be more serious. For example, a case study highlighted a 67-year-old man who developed severe, chronic diarrhea and lost weight over nine months while taking losartan. His symptoms resolved within a week after stopping the medication.
Research suggests that losartan may cause diarrhea by affecting intestinal motility. A preclinical study found that losartan modulates intestinal smooth muscle contraction, potentially interfering with normal digestive processes.
To manage diarrhea, drink plenty of fluids to stay hydrated and avoid caffeinated or sugary drinks, which can worsen diarrhea.
Joint or Muscle Pain
Some people experience joint or muscle pain while taking losartan. Although less common, it can be bothersome. Losartan, while protective in some forms of muscular dystrophy, may worsen muscle damage in specific conditions.
For instance, a study using a mouse model of Limb-Girdle Muscular Dystrophy type 2B (LGMD2B) found that losartan treatment increased muscle wasting and fibrosis in affected muscles by up to 142%.
To handle joint or muscle pain, try gentle stretching or light exercise. Over-the-counter pain relievers like acetaminophen can also help. Avoid NSAIDs like ibuprofen unless your doctor approves.
Back Pain
Back pain affects about 2% of losartan users, slightly higher than the 1% reported in placebo groups. Although it’s usually mild, back pain can interfere with your daily activities.
Using heat packs or doing gentle back exercises might provide relief. If the pain persists, consult your doctor.
Upper Respiratory Infections
Losartan users might catch a cold and experience symptoms like a runny nose, nasal congestion, or a sore throat. In clinical studies, 6.5% of patients treated with losartan reported upper respiratory infections compared to 5.6% in the placebo group. This slight increase was not statistically significant, suggesting no strong link between losartan and these infections.
Additionally, no dose-related trends were identified, meaning the occurrence of upper respiratory infections didn’t consistently change with different doses of losartan.
To manage a cold, stay hydrated, get plenty of rest, and use over-the-counter cold remedies. If your symptoms worsen or don’t improve, see your doctor.
Nasal Congestion
About 2% of people taking losartan experience a stuffy nose, often linked to upper respiratory infections. Nasal congestion from losartan is usually mild, but if it becomes severe or doesn’t go away, talk to your healthcare provider.
Your provider might recommend using a Neti Pot or a nasal spray like fluticasone propionate (Flonase). Oral decongestants, such as pseudoephedrine (Sudafed), are generally avoided because they can increase blood pressure.
Fatigue
Feeling tired, or fatigue, is a recognized side effect of losartan and similar blood pressure medications. It’s most common when you start losartan or after a dosage increase. Fortunately, this effect often lessens as your body adjusts and your blood pressure stabilizes.
To manage fatigue, engage in regular exercise and maintain a balanced diet rich in vitamins and minerals to support your energy levels.
If fatigue becomes severe or gets worse, consult your healthcare provider. They might adjust your dose or suggest an alternative treatment that better suits your needs.
Serious Side Effects of Losartan and When to Seek Help
Taking losartan usually causes only mild side effects. But sometimes, serious problems can happen.
Yellowing of Skin or Eyes (Jaundice)
Losartan can rarely cause jaundice and liver inflammation. For example, a 46-year-old man felt very tired, lost his appetite, felt sick, and noticed his skin and eyes turned yellow. This happened two weeks after he switched from enalapril to losartan for high blood pressure.
He didn’t have any liver problems before, didn’t drink too much alcohol, and had no risk factors for hepatitis.
Two weeks after his symptoms started, doctors found he had jaundice, a mild fever of 37.7°C, and some liver tenderness.
Doctors stopped losartan and switched him to atenolol. He got better quickly, and his symptoms and blood tests returned to normal within four months. When he took a lower dose of losartan again, his symptoms and jaundice came back after three weeks. Losartan was stopped again, and he fully recovered in six weeks. This shows the potential for losartan to cause liver problems.
If you take losartan and notice yellowing of your skin or eyes, feel very tired, or have persistent nausea, stop taking the medicine and talk to your doctor right away. You might need a different treatment to protect your liver.
If you see these signs, contact your doctor immediately or call emergency services.
Severe Stomach Pain
Losartan can sometimes cause serious stomach pain and pancreatitis. For example, a 71-year-old woman with high blood pressure, anxiety, and hypothyroidism had sharp pain in her middle abdomen that spread to her back. She also felt nauseous and was vomiting.
She had similar symptoms four weeks earlier, which were treated without surgery. After many tests, doctors couldn’t find another reason for her pancreatitis. She started taking losartan again after leaving the hospital.
Later, she was hospitalized again. Scans showed her pancreas was inflamed with fluid around it. Tests ruled out gallstones and other common causes of pancreatitis. Doctors stopped her losartan, and her symptoms went away. When she took losartan again, her symptoms came back within weeks. This showed that losartan was likely causing her pancreatitis.
It is not yet fully understood how losartan causes pancreatitis. It might affect the pancreatic ducts or directly harm pancreatic cells. Stopping losartan usually makes the symptoms go away. If you have severe stomach pain or signs of pancreatitis while taking losartan, contact your healthcare provider immediately.
Your doctor might suggest switching to a different medicine, like a calcium channel blocker, to prevent this from happening again.
High Blood Potassium Levels (Hyperkalemia)
Losartan can sometimes raise your blood potassium levels, especially if you have kidney disease, diabetes, or take other medications like a potassium-sparing diuretic. Losartan lowers aldosterone, which helps your body remove potassium. When aldosterone is reduced, potassium can build up in your blood.
Studies show that potassium levels can rise significantly while on losartan. In some cases, doctors might need to stop the medication to prevent serious issues.
To keep this risk in check, it’s important to check your potassium and kidney function regularly. Also, be mindful of your diet and try to limit foods high in potassium.
If you feel muscle weakness, extreme tiredness, or irregular heartbeats, tell your doctor immediately. These could be signs of high potassium levels that need immediate attention.
Low Blood Pressure (Hypotension)
Losartan can sometimes cause your blood pressure to drop too low, especially if you’re dehydrated, taking high doses, or have other health conditions like a sudden illness.
Studies have found that people taking losartan may experience more episodes of hypotension compared to those not taking it, particularly in hospital settings with illnesses like COVID-19 or pneumonia.
This happens because losartan widens your blood vessels, which can lower your blood pressure too much if you’re sensitive. Low blood pressure can make you feel dizzy, cause you to faint, or even lead to shock in severe cases.
If you’re at risk, your blood pressure should be checked regularly. If you feel dizzy or lightheaded, lie down and raise your legs. If these symptoms continue or happen often, contact your doctor right away. They might need to adjust your medication or consider other treatments.
Rare Side Effects of Losartan and Associated Risks
While taking losartan, some people may experience rare but serious side effects. Knowing these can help you act quickly and prevent complications.
Let’s look at these rare side effects, their risks, and when to seek medical help.
Photosensitivity (Increased Sensitivity to Sunlight)
Some people taking losartan have become more sensitive to sunlight, a condition called photosensitivity.
A study reviewed reports and found that losartan was responsible for about a quarter of these cases. Photosensitivity means you might get severe sunburn or skin irritation from just a little sun exposure. This can lead to skin damage.
To stay safe, use sunscreen with SPF 30 or higher, wear protective clothing, and try to stay out of the sun as much as possible. If you experience unusual skin reactions, talk to your healthcare provider.
Rare Kidney Complications
Losartan can affect kidney function, especially in people with certain health conditions. For example, those with severe heart failure or kidney artery problems are at higher risk.
A study found that about 10.5% of elderly patients with congestive heart failure experienced kidney issues while taking losartan, similar to those taking other medications like captopril. In some cases, stopping losartan helped kidney function return to normal.
This means losartan can pose risks to the kidneys, particularly if you already have kidney problems. Regular kidney function tests are important if you’re on losartan, especially if you have existing kidney issues. Consult your doctor immediately after knowing this complication.
Hemolysis (Destruction of Red Blood Cells)
Hemolysis is a rare condition where your red blood cells are destroyed. You might feel extremely tired, have pale skin, a fast heartbeat, or notice dark-colored urine. These symptoms can lead to anemia and other serious issues, so don’t ignore them. If you experience these signs, seek medical attention right away.
Losartan can sometimes cause hemolysis. For example, a 23-year-old man took losartan for three months and developed severe anemia. His hemoglobin level dropped to 8.1 g/dL, much lower than normal. He also had painful skin lesions from vasculitis. His symptoms only started to improve after he stopped taking losartan. Although this side effect is rare, it shows why it’s important to monitor for unexpected reactions when using medications like losartan.
If you’re taking losartan and notice symptoms like extreme fatigue or pale skin, tell your doctor immediately. Early intervention can prevent complications and help you recover faster.
Angioedema (Severe Swelling Under the Skin)
Angioedema is a rare but serious reaction that causes severe swelling in your face, lips, tongue, or throat, making breathing hard. This can be life-threatening and needs immediate medical attention. Call emergency services immediately if you experience significant swelling or difficulty breathing.
Losartan has been linked to rare cases of angioedema. For instance, a 60-year-old man taking losartan developed severe swelling in his face, tongue, and lips. He also had trouble breathing. Even after receiving antihistamines and corticosteroids, his symptoms got worse, and he needed to be intubated to keep his airway open. His condition only improved after he stopped taking losartan. Angiotensin receptor blockers and ACE inhibitors are both notorious for the potential to induce angioedema.
If you’re on losartan and notice swelling, especially around your face or throat, stop taking the medication and seek medical help immediately. Being aware and acting quickly is crucial, as angioedema can quickly become life-threatening.
Wrap Up
Losartan helps control your high blood pressure and protect your kidneys, but it can cause some side effects. You might feel dizzy, especially when you stand up quickly. Headaches and tiredness are common, but they usually get better over time.
If you experience severe stomach pain or notice swelling in your face or throat, stop taking losartan and immediately see your doctor.
Monitor your potassium levels by eating a balanced diet and getting regular blood tests. Losartan can make your skin more sensitive to the sun, so wear protective clothing and sunscreen.
Frequently Asked Questions
Does Losartan cause weight changes?
No, Losartan is not linked to weight gain or loss. However, swelling (edema) could indirectly cause weight changes.
Is Losartan safe for people with kidney problems?
Losartan may increase the risk of kidney issues. If you have kidney problems, consult your doctor before starting it.
Does Losartan interact with alcohol?
Yes. Both can lower blood pressure and cause dizziness. Limit alcohol while taking Losartan.
Can Losartan cause allergic reactions?
Yes, though rare. Symptoms include rash, itching, swelling, or difficulty breathing. Seek immediate help if these occur.
How should I store Losartan?
Store it at room temperature, away from moisture and direct sunlight. Keep it out of reach of children.
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