Losartan 50mg Tablets
WARNING: Do not take if you are pregnant. Use during pregnancy may cause birth defects or loss of the unborn baby. If you get pregnant or plan on getting pregnant while taking this drug, call your doctor right away. @ COMMON USES: It is used to treat high blood pressure.It is used to protect kidney function in patients with diabetes who have protein loss.It is used to lower the chance of stroke in people with high blood pressure and a heart problem called left ventricular hypertrophy. This drug may not help lower the chance of stroke in Black patients with these health problems.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Antihypertensive
Pharmacologic Class
Angiotensin II Receptor Blocker (ARB)
Pregnancy Category
Not available
FDA Approved
Apr 1995
DEA Schedule
Not Controlled
Overview
What is this medicine?
Losartan is a medication used to lower high blood pressure. It works by blocking a natural substance in your body that can narrow blood vessels. By relaxing blood vessels, it helps blood flow more easily, which lowers your blood pressure and reduces the strain on your heart. It's also used to protect kidneys in people with diabetes and high blood pressure, and to reduce the risk of stroke in certain patients.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take your medication with or without food, as directed. It's essential to continue taking this medication as prescribed by your doctor or healthcare provider, even if you're feeling well.
If you have difficulty swallowing pills, a liquid suspension can be prepared. Consult with your doctor or pharmacist to discuss this option. If a liquid suspension is made, be sure to shake it well before each use. When measuring liquid doses, use the measuring device that comes with the medication. If one is not provided, ask your pharmacist for a suitable measuring device.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light, and in a dry place. Avoid storing it in a bathroom. Keep the lid tightly closed. If a liquid suspension is prepared from the tablets, store it in the refrigerator. Do not freeze. Discard any unused portion after 28 days.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses.
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take your medication with or without food, as directed. It's essential to continue taking this medication as prescribed by your doctor or healthcare provider, even if you're feeling well.
If you have difficulty swallowing pills, a liquid suspension can be prepared. Consult with your doctor or pharmacist to discuss this option. If a liquid suspension is made, be sure to shake it well before each use. When measuring liquid doses, use the measuring device that comes with the medication. If one is not provided, ask your pharmacist for a suitable measuring device.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light, and in a dry place. Avoid storing it in a bathroom. Keep the lid tightly closed. If a liquid suspension is prepared from the tablets, store it in the refrigerator. Do not freeze. Discard any unused portion after 28 days.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses.
Lifestyle & Tips
- Continue to follow a healthy diet, including limiting sodium intake.
- Engage in regular physical activity as advised by your doctor.
- Limit alcohol consumption.
- Do not use potassium supplements or salt substitutes containing potassium without consulting your doctor.
- Monitor your blood pressure regularly at home as instructed.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
50 mg once daily
Dose Range:
25 - 100 mg
Condition-Specific Dosing:
hypertension:
Initial 50 mg once daily; usual maintenance 25-100 mg once daily. May be given once or twice daily.
diabetic_nephropathy:
Initial 50 mg once daily; may be increased to 100 mg once daily based on blood pressure response.
stroke_risk_reduction_with_LVH:
Initial 50 mg once daily; may be increased to 100 mg once daily based on blood pressure response.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Hypertension (≥6 years): Initial 0.7 mg/kg once daily (max 50 mg); may be titrated up to 1.4 mg/kg once daily (max 100 mg).
Adolescent:
Hypertension (≥6 years): Initial 0.7 mg/kg once daily (max 50 mg); may be titrated up to 1.4 mg/kg once daily (max 100 mg).
Dose Adjustments
Renal Impairment:
Mild:
No initial dose adjustment required.
Moderate:
No initial dose adjustment required.
Severe:
Consider lower initial dose (e.g., 25 mg once daily) for patients with severe renal impairment (CrCl <30 mL/min).
Dialysis:
Consider lower initial dose (e.g., 25 mg once daily); Losartan and its active metabolite are not removed by hemodialysis.
Hepatic Impairment:
Mild:
Consider lower initial dose (e.g., 25 mg once daily).
Moderate:
Consider lower initial dose (e.g., 25 mg once daily).
Severe:
Not recommended due to significantly increased plasma concentrations of Losartan and its active metabolite.
Pharmacology
Mechanism of Action
Losartan is a selective, competitive antagonist of the angiotensin II type 1 (AT1) receptor. It blocks the binding of angiotensin II to the AT1 receptor found in many tissues (e.g., vascular smooth muscle, adrenal gland), thereby inhibiting the vasoconstrictive and aldosterone-secreting effects of angiotensin II. This leads to vasodilation, reduced aldosterone secretion, and decreased sodium and water reabsorption, resulting in a reduction in blood pressure.
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 33%
Tmax:
Losartan: 1 hour; Active metabolite (E-3174): 3-4 hours
FoodEffect:
Food slows absorption and decreases Cmax but has no clinically significant effect on AUC.
Distribution:
Vd:
Losartan: 34 liters; Active metabolite (E-3174): 12 liters
ProteinBinding:
>98% (Losartan and E-3174), primarily to albumin
CnssPenetration:
Limited
Elimination:
HalfLife:
Losartan: Approximately 2 hours; Active metabolite (E-3174): 6-9 hours
Clearance:
Losartan: 600 mL/min (renal 74 mL/min); E-3174: 50 mL/min (renal 26 mL/min)
ExcretionRoute:
Biliary (feces) and renal (urine)
Unchanged:
Approximately 4% (Losartan) and 6% (E-3174) excreted unchanged in urine.
Pharmacodynamics
OnsetOfAction:
Within 1 hour
PeakEffect:
3-6 hours
DurationOfAction:
24 hours
Safety & Warnings
BLACK BOX WARNING
When pregnancy is detected, discontinue Losartan as soon as possible. Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus.
Side Effects
Serious Side Effects: Seek Medical Help Immediately
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention right away:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of kidney problems, including:
+ Inability to pass urine
+ Changes in urine output
+ Blood in the urine
+ Sudden weight gain
Signs of high potassium levels, such as:
+ Abnormal heartbeat
+ Confusion
+ Weakness, lightheadedness, or dizziness
+ Feeling like passing out
+ Numbness or tingling
+ Shortness of breath
Signs of low blood sugar, including:
+ Dizziness
+ Headache
+ Feeling sleepy or weak
+ Shaking
+ Rapid heartbeat
+ Confusion
+ Hunger
+ Sweating
Severe dizziness or fainting
Chest pain
Swelling in the arms or legs
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Signs of a common cold
Feeling dizzy, tired, or weak
Diarrhea
Back pain
Stuffy nose
This is not an exhaustive list of possible side effects. If you have questions or concerns, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention right away:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of kidney problems, including:
+ Inability to pass urine
+ Changes in urine output
+ Blood in the urine
+ Sudden weight gain
Signs of high potassium levels, such as:
+ Abnormal heartbeat
+ Confusion
+ Weakness, lightheadedness, or dizziness
+ Feeling like passing out
+ Numbness or tingling
+ Shortness of breath
Signs of low blood sugar, including:
+ Dizziness
+ Headache
+ Feeling sleepy or weak
+ Shaking
+ Rapid heartbeat
+ Confusion
+ Hunger
+ Sweating
Severe dizziness or fainting
Chest pain
Swelling in the arms or legs
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Signs of a common cold
Feeling dizzy, tired, or weak
Diarrhea
Back pain
Stuffy nose
This is not an exhaustive list of possible side effects. If you have questions or concerns, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or fainting (especially when standing up)
- Swelling of the face, lips, tongue, or throat (signs of angioedema)
- Difficulty breathing or swallowing
- Yellowing of the skin or eyes (jaundice)
- Unusual tiredness or weakness
- Irregular heartbeat or palpitations
- Muscle weakness or cramps (signs of high potassium)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
Existing kidney problems, as this may affect the medication's safety and efficacy.
* If you are taking a medication that contains aliskiren, especially if you have diabetes or kidney problems.
Special Considerations for Children:
If your child is under 6 years of age, do not administer this medication, as it is not recommended for children younger than 6 years old.
Additional Guidance:
This list is not exhaustive, and it is crucial to discuss all your medications (including prescription, over-the-counter, natural products, and vitamins) and health issues with your doctor and pharmacist. This will help ensure that it is safe to take this medication in conjunction with your other treatments. Never start, stop, or adjust the dosage of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
Existing kidney problems, as this may affect the medication's safety and efficacy.
* If you are taking a medication that contains aliskiren, especially if you have diabetes or kidney problems.
Special Considerations for Children:
If your child is under 6 years of age, do not administer this medication, as it is not recommended for children younger than 6 years old.
Additional Guidance:
This list is not exhaustive, and it is crucial to discuss all your medications (including prescription, over-the-counter, natural products, and vitamins) and health issues with your doctor and pharmacist. This will help ensure that it is safe to take this medication in conjunction with your other treatments. Never start, stop, or adjust the dosage of any medication without first consulting your doctor.
Precautions & Cautions
Important Warnings and Precautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
Caution with Daily Activities
Until you know how this medication affects you, avoid driving and other tasks that require alertness. To minimize the risk of dizziness or fainting, rise slowly from a sitting or lying position, and be cautious when climbing stairs.
Monitoring Your Condition
Regularly check your blood pressure as directed by your healthcare provider. Additionally, have your blood work checked as instructed by your doctor, and discuss the results with them.
Interactions with Other Substances
If you are taking a salt substitute containing potassium, a potassium-sparing diuretic, or a potassium product, consult your doctor. Similarly, if you are on a low-salt or salt-free diet, discuss this with your doctor.
High Blood Pressure and Over-the-Counter Products
If you have high blood pressure and are taking this medication, talk to your doctor before using over-the-counter products that may increase blood pressure, such as:
- Cough or cold medications
- Diet pills
- Stimulants
- Non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen
- Certain natural products or aids
Alcohol Consumption
Discuss your alcohol consumption with your doctor before drinking.
Hot Weather and Physical Activity
Be cautious in hot weather or during physical activity, and drink plenty of fluids to prevent dehydration.
Signs of Low Blood Pressure
Inform your doctor if you experience excessive sweating, fluid loss, vomiting, or loose stools, as these may lead to low blood pressure.
Breastfeeding
If you are breastfeeding, consult your doctor to discuss any potential risks to your baby.
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
Caution with Daily Activities
Until you know how this medication affects you, avoid driving and other tasks that require alertness. To minimize the risk of dizziness or fainting, rise slowly from a sitting or lying position, and be cautious when climbing stairs.
Monitoring Your Condition
Regularly check your blood pressure as directed by your healthcare provider. Additionally, have your blood work checked as instructed by your doctor, and discuss the results with them.
Interactions with Other Substances
If you are taking a salt substitute containing potassium, a potassium-sparing diuretic, or a potassium product, consult your doctor. Similarly, if you are on a low-salt or salt-free diet, discuss this with your doctor.
High Blood Pressure and Over-the-Counter Products
If you have high blood pressure and are taking this medication, talk to your doctor before using over-the-counter products that may increase blood pressure, such as:
- Cough or cold medications
- Diet pills
- Stimulants
- Non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen
- Certain natural products or aids
Alcohol Consumption
Discuss your alcohol consumption with your doctor before drinking.
Hot Weather and Physical Activity
Be cautious in hot weather or during physical activity, and drink plenty of fluids to prevent dehydration.
Signs of Low Blood Pressure
Inform your doctor if you experience excessive sweating, fluid loss, vomiting, or loose stools, as these may lead to low blood pressure.
Breastfeeding
If you are breastfeeding, consult your doctor to discuss any potential risks to your baby.
Overdose Information
Overdose Symptoms:
- Profound hypotension (low blood pressure)
- Tachycardia (rapid heartbeat)
- Bradycardia (slow heartbeat)
What to Do:
If you suspect an overdose, seek immediate medical attention. Call 911 or your local emergency number. For poison control, call 1-800-222-1222. Treatment is supportive and symptomatic; lay the patient supine with legs elevated, administer IV fluids if hypotensive. Losartan and its active metabolite are not removed by hemodialysis.
Drug Interactions
Contraindicated Interactions
- Aliskiren (in patients with diabetes mellitus or moderate to severe renal impairment (GFR <60 mL/min/1.73 m²))
Major Interactions
- Potassium-sparing diuretics (e.g., spironolactone, triamterene, amiloride)
- Potassium supplements
- Salt substitutes containing potassium
- NSAIDs (including selective COX-2 inhibitors) - increased risk of renal impairment, reduced antihypertensive effect
- Lithium (increased serum lithium concentrations and toxicity)
- ACE inhibitors (increased risk of hyperkalemia, hypotension, and renal impairment)
Moderate Interactions
- CYP2C9 inhibitors (e.g., fluconazole, amiodarone) - may decrease formation of active metabolite (E-3174)
- CYP3A4 inhibitors (e.g., ketoconazole, erythromycin) - less significant effect on active metabolite formation
- Other antihypertensive agents (additive hypotensive effect)
Minor Interactions
- Not available
Monitoring
Baseline Monitoring
Blood Pressure (BP)
Rationale: To establish baseline and guide initial dosing.
Timing: Prior to initiation of therapy.
Serum Creatinine (SCr) and Blood Urea Nitrogen (BUN)
Rationale: To assess baseline renal function, as Losartan can affect renal hemodynamics.
Timing: Prior to initiation of therapy.
Serum Potassium (K+)
Rationale: To assess baseline potassium levels, as Losartan can cause hyperkalemia.
Timing: Prior to initiation of therapy.
Routine Monitoring
Blood Pressure (BP)
Frequency: Regularly (e.g., daily at home, at each clinic visit)
Target: <130/80 mmHg (or individualized target based on guidelines/patient condition)
Action Threshold: If BP remains uncontrolled or drops excessively, adjust dose or consider additional therapy.
Serum Creatinine (SCr) and Blood Urea Nitrogen (BUN)
Frequency: Periodically (e.g., 1-2 weeks after initiation or dose change, then every 3-6 months, or more frequently in patients with pre-existing renal impairment or on concomitant nephrotoxic drugs)
Target: Within normal limits or stable from baseline
Action Threshold: Significant increase (e.g., >30% above baseline or progressive increase) may indicate renal dysfunction; consider dose reduction or discontinuation.
Serum Potassium (K+)
Frequency: Periodically (e.g., 1-2 weeks after initiation or dose change, then every 3-6 months, or more frequently in patients at risk for hyperkalemia)
Target: 3.5-5.0 mEq/L
Action Threshold: K+ >5.5 mEq/L may require dose reduction, discontinuation, or specific management for hyperkalemia.
Symptom Monitoring
- Dizziness or lightheadedness (especially upon standing, indicative of hypotension)
- Swelling of face, lips, tongue, or throat (signs of angioedema)
- Difficulty breathing or swallowing (signs of angioedema)
- Symptoms of hyperkalemia (e.g., muscle weakness, fatigue, palpitations, irregular heartbeat)
- Signs of worsening renal function (e.g., decreased urine output, swelling in ankles/feet)
Special Patient Groups
Pregnancy
Contraindicated in the second and third trimesters of pregnancy due to significant risk of fetal injury and death. Discontinue as soon as pregnancy is detected. Use in the first trimester is generally avoided due to potential risks, though data are less conclusive than for later trimesters.
Trimester-Specific Risks:
First Trimester:
Limited human data; potential for fetal harm cannot be excluded. Generally avoided.
Second Trimester:
High risk of fetal renal dysfunction, oligohydramnios, fetal lung hypoplasia, skeletal deformations, and death.
Third Trimester:
High risk of fetal renal dysfunction, oligohydramnios, fetal lung hypoplasia, skeletal deformations, and death.
Lactation
Not recommended during breastfeeding. It is unknown if Losartan or its active metabolite are excreted in human milk. Due to the potential for serious adverse effects on the breastfed infant, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.
Infant Risk:
Potential for serious adverse effects (e.g., hypotension, renal effects) in the infant. Risk level L3 (Moderately Safe) or L4 (Potentially Hazardous) depending on source, but caution is advised.
Pediatric Use
Approved for hypertension in children 6 years and older. Safety and efficacy in children younger than 6 years have not been established. Dosing is weight-based.
Geriatric Use
No initial dose adjustment is generally necessary for elderly patients. However, elderly patients may be more sensitive to the hypotensive effects and may have age-related decreases in renal function, requiring careful monitoring of blood pressure, renal function, and electrolytes.
Clinical Information
Clinical Pearls
- Losartan is often chosen for patients who develop a cough with ACE inhibitors, as ARBs typically do not cause this side effect.
- The full antihypertensive effect may take 3-6 weeks to develop.
- Patients should be advised to avoid sudden discontinuation of Losartan, as this could lead to a rebound increase in blood pressure.
- Monitor for signs of angioedema, though it is less common with ARBs than with ACE inhibitors.
- Educate patients on the importance of avoiding potassium supplements and salt substitutes unless specifically instructed by their healthcare provider, due to the risk of hyperkalemia.
Alternative Therapies
- Other Angiotensin II Receptor Blockers (ARBs) (e.g., Valsartan, Candesartan, Olmesartan, Irbesartan)
- Angiotensin-Converting Enzyme (ACE) Inhibitors (e.g., Lisinopril, Enalapril, Ramipril)
- Calcium Channel Blockers (e.g., Amlodipine, Nifedipine, Diltiazem)
- Thiazide Diuretics (e.g., Hydrochlorothiazide, Chlorthalidone)
- Beta-blockers (e.g., Metoprolol, Atenolol)
- Other classes of antihypertensives depending on patient comorbidities and guidelines.
Cost & Coverage
Average Cost:
$10 - $30 per 30 tablets (generic 50mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 (Generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about this medication, don't hesitate to discuss them with your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.