Labetalol 5mg/ml Inj, 40ml
It is used to treat high blood pressure.
Drug Class
Antihypertensive
Pharmacologic Class
Alpha- and Beta-Adrenergic Blocker
Pregnancy Category
C
FDA Approved
Aug 1984
DEA Schedule
Not Controlled
Overview
What is this medicine?
Labetalol is a medicine given by injection, usually in a hospital setting, to quickly lower very high blood pressure. It works by relaxing blood vessels and slowing the heart rate.
How to Use This Medicine
To use this medication correctly, follow your doctor's instructions and carefully read all accompanying information. Take this medication exactly as directed, and adhere to all guidelines provided. This drug is administered intravenously over a specified period.
If you need to store this medication at home, consult with your doctor, nurse, or pharmacist to determine the proper storage procedure.
If you miss a dose, contact your doctor promptly to receive guidance on the appropriate course of action.
If you need to store this medication at home, consult with your doctor, nurse, or pharmacist to determine the proper storage procedure.
If you miss a dose, contact your doctor promptly to receive guidance on the appropriate course of action.
Lifestyle & Tips
- This medication is typically used in acute, severe situations where lifestyle changes are not immediately applicable. However, for long-term blood pressure control, a healthy diet (low sodium), regular exercise, maintaining a healthy weight, and avoiding smoking and excessive alcohol are important.
- Report any dizziness or lightheadedness, especially when changing positions (e.g., standing up).
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
Initial 20 mg IV bolus, then 40-80 mg IV every 10 minutes as needed, or continuous infusion 2 mg/min, titrated.
Dose Range:
20 - 300 mg
Condition-Specific Dosing:
hypertensiveCrisis:
Initial 20 mg IV bolus, then 40-80 mg IV every 10 minutes (max total 300 mg) OR continuous infusion 2 mg/min, titrated up to 300 mg total or max 300 mg/hr.
Pediatric Dosing
Neonatal:
Not established (off-label use in critical care, typically 0.2-0.5 mg/kg/dose IV, max 3 mg/kg/day)
Infant:
Not established (off-label use in critical care, typically 0.2-0.5 mg/kg/dose IV, max 3 mg/kg/day)
Child:
Not established (off-label use in critical care, typically 0.2-0.5 mg/kg/dose IV, max 3 mg/kg/day)
Adolescent:
Not established (off-label use in critical care, typically 0.2-0.5 mg/kg/dose IV, max 3 mg/kg/day)
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment needed.
Moderate:
No specific adjustment needed.
Severe:
Use with caution; monitor blood pressure and heart rate closely. No specific dose adjustment guidelines, but may accumulate in severe renal failure.
Dialysis:
Labetalol is not significantly removed by hemodialysis. No specific supplemental dose needed post-dialysis, but monitor closely.
Hepatic Impairment:
Mild:
Use with caution.
Moderate:
Use with caution; consider lower initial doses and slower titration due to extensive hepatic metabolism.
Severe:
Use with caution; consider lower initial doses and slower titration due to extensive hepatic metabolism. May require significant dose reduction.
Pharmacology
Mechanism of Action
Labetalol is a selective alpha-1 adrenergic receptor blocker and a non-selective beta-adrenergic receptor blocker. It competitively blocks alpha-1 receptors in vascular smooth muscle, leading to vasodilation and reduced peripheral vascular resistance. It also blocks beta-1 receptors in the heart, reducing heart rate and myocardial contractility, and beta-2 receptors in bronchial and vascular smooth muscle. The ratio of alpha- to beta-blockade is approximately 1:7 for IV administration.
Pharmacokinetics
Absorption:
Bioavailability:
100% (IV administration)
Tmax:
Immediate (IV bolus)
FoodEffect:
Not applicable for IV formulation
Distribution:
Vd:
3.2-16 L/kg
ProteinBinding:
Approximately 50%
CnssPenetration:
Limited
Elimination:
HalfLife:
Approximately 5.5 hours
Clearance:
Approximately 1.7 L/min
ExcretionRoute:
Renal (55-60%), Fecal (30%)
Unchanged:
Less than 5% (renal)
Pharmacodynamics
OnsetOfAction:
2-5 minutes (IV)
PeakEffect:
5-15 minutes (IV)
DurationOfAction:
2-4 hours (IV)
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Attention 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 help 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
Severe dizziness or fainting
Slow heartbeat
Abnormal burning, numbness, or tingling sensations
Erectile dysfunction
Heart failure, which can be a new condition or a worsening of existing heart disease. If you have a history of heart disease, inform your doctor. Seek immediate medical attention if you experience:
+ Shortness of breath
+ Sudden significant weight gain
+ Irregular heartbeat
+ New or worsening swelling in the arms or legs
Liver problems, which can be rare but potentially life-threatening. Contact your doctor right away if you notice:
+ Dark urine
+ Fatigue
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellowing of the skin or eyes
Other Possible Side Effects
Like all medications, this drug can cause side effects, although many people may not experience any or may only have mild symptoms. If you are bothered by any of the following side effects or if they persist, contact your doctor or seek medical help:
Dizziness
Fatigue
Weakness
Upset stomach
Tingling sensation on the scalp
* Stuffy nose
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, 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 help 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
Severe dizziness or fainting
Slow heartbeat
Abnormal burning, numbness, or tingling sensations
Erectile dysfunction
Heart failure, which can be a new condition or a worsening of existing heart disease. If you have a history of heart disease, inform your doctor. Seek immediate medical attention if you experience:
+ Shortness of breath
+ Sudden significant weight gain
+ Irregular heartbeat
+ New or worsening swelling in the arms or legs
Liver problems, which can be rare but potentially life-threatening. Contact your doctor right away if you notice:
+ Dark urine
+ Fatigue
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellowing of the skin or eyes
Other Possible Side Effects
Like all medications, this drug can cause side effects, although many people may not experience any or may only have mild symptoms. If you are bothered by any of the following side effects or if they persist, contact your doctor or seek medical help:
Dizziness
Fatigue
Weakness
Upset stomach
Tingling sensation on the scalp
* Stuffy nose
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, 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
- Very slow heartbeat
- Difficulty breathing or wheezing
- Swelling in ankles or feet
- Unusual tiredness or weakness
- Yellowing of skin or eyes (jaundice)
- Dark urine or persistent nausea/vomiting (signs of liver problems)
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.
If you have low blood pressure.
If you have a history of certain health conditions, including:
+ Breathing problems, such as asthma or chronic obstructive pulmonary disease (COPD)
+ Heart block
+ Heart failure (weak heart)
+ Shock caused by heart problems
+ Slow heartbeat
If you are currently taking diltiazem or verapamil.
Please note that this is not an exhaustive list of all potential interactions. To ensure your safety, it is crucial to discuss all of your medications (prescription, over-the-counter, natural products, and vitamins) and health problems with your doctor and pharmacist. Before starting, stopping, or changing the dose of any medication, consult with your doctor to confirm that it is safe to do so in conjunction with this medication.
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.
If you have low blood pressure.
If you have a history of certain health conditions, including:
+ Breathing problems, such as asthma or chronic obstructive pulmonary disease (COPD)
+ Heart block
+ Heart failure (weak heart)
+ Shock caused by heart problems
+ Slow heartbeat
If you are currently taking diltiazem or verapamil.
Please note that this is not an exhaustive list of all potential interactions. To ensure your safety, it is crucial to discuss all of your medications (prescription, over-the-counter, natural products, and vitamins) and health problems with your doctor and pharmacist. Before starting, stopping, or changing the dose of any medication, consult with your doctor to confirm that it is safe to do so in conjunction with this medication.
Precautions & Cautions
Important Warnings and Cautions
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 activities 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
Follow your doctor's instructions for checking your blood pressure and heart rate. Additionally, have your blood work and other laboratory tests done as directed by your doctor.
Interference with Lab Tests
This medication may affect certain laboratory tests. Be sure to inform all your healthcare providers and laboratory personnel that you are taking this medication.
Risk of Low Blood Sugar
This medication may mask symptoms of low blood sugar, such as rapid heartbeat, which can increase the risk of severe or prolonged low blood sugar. This risk is higher in people with diabetes, children, and those who are fasting, undergoing surgery, or experiencing nausea and vomiting. If you have questions or concerns, discuss them with your doctor.
Managing Diabetes
If you have high blood sugar (diabetes), closely monitor your blood sugar levels while taking this medication.
Discontinuing the Medication
Do not stop taking this medication abruptly, as this can lead to worsened chest pain or even heart attack, especially in people with certain types of heart disease. To avoid side effects, your doctor will instruct you on how to gradually discontinue the medication. If you experience new or worsening chest pain or other heart problems, seek medical attention immediately.
Allergic Reactions
If you have a history of severe allergic reactions, consult your doctor, as you may be at risk of an even more severe reaction. If you use epinephrine to treat allergic reactions, discuss this with your doctor, as epinephrine may be less effective while taking this medication.
Eye Procedures
If you are scheduled to undergo cataract surgery or other eye procedures, inform your doctor.
Interactions with Other Medications
Before using over-the-counter (OTC) products that may increase blood pressure, such as cough and cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, and certain natural products or aids, consult your doctor.
Special Considerations for Older Adults
If you are 60 years or older, use this medication with caution, as you may be more susceptible to side effects.
Pregnancy and Breastfeeding
If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks of this medication with your doctor.
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 activities 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
Follow your doctor's instructions for checking your blood pressure and heart rate. Additionally, have your blood work and other laboratory tests done as directed by your doctor.
Interference with Lab Tests
This medication may affect certain laboratory tests. Be sure to inform all your healthcare providers and laboratory personnel that you are taking this medication.
Risk of Low Blood Sugar
This medication may mask symptoms of low blood sugar, such as rapid heartbeat, which can increase the risk of severe or prolonged low blood sugar. This risk is higher in people with diabetes, children, and those who are fasting, undergoing surgery, or experiencing nausea and vomiting. If you have questions or concerns, discuss them with your doctor.
Managing Diabetes
If you have high blood sugar (diabetes), closely monitor your blood sugar levels while taking this medication.
Discontinuing the Medication
Do not stop taking this medication abruptly, as this can lead to worsened chest pain or even heart attack, especially in people with certain types of heart disease. To avoid side effects, your doctor will instruct you on how to gradually discontinue the medication. If you experience new or worsening chest pain or other heart problems, seek medical attention immediately.
Allergic Reactions
If you have a history of severe allergic reactions, consult your doctor, as you may be at risk of an even more severe reaction. If you use epinephrine to treat allergic reactions, discuss this with your doctor, as epinephrine may be less effective while taking this medication.
Eye Procedures
If you are scheduled to undergo cataract surgery or other eye procedures, inform your doctor.
Interactions with Other Medications
Before using over-the-counter (OTC) products that may increase blood pressure, such as cough and cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, and certain natural products or aids, consult your doctor.
Special Considerations for Older Adults
If you are 60 years or older, use this medication with caution, as you may be more susceptible to side effects.
Pregnancy and Breastfeeding
If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks of this medication with your doctor.
Overdose Information
Overdose Symptoms:
- Severe hypotension (very low blood pressure)
- Profound bradycardia (very slow heart rate)
- Cardiogenic shock
- Bronchospasm
- Acute cardiac failure
- Convulsions
What to Do:
Seek immediate medical attention. Management is supportive and symptomatic. Atropine for bradycardia, vasopressors for hypotension, glucagon for refractory bradycardia/hypotension, bronchodilators for bronchospasm, diuretics for heart failure. Call 1-800-222-1222 (Poison Control).
Drug Interactions
Contraindicated Interactions
- Bronchial asthma
- Overt cardiac failure
- Greater than first-degree heart block
- Cardiogenic shock
- Severe bradycardia
- Hypersensitivity to labetalol or its components
Major Interactions
- Calcium channel blockers (e.g., verapamil, diltiazem): Increased risk of bradycardia, AV block, and heart failure.
- Other beta-blockers: Additive effects, increased risk of bradycardia and hypotension.
- Tricyclic antidepressants: May increase risk of tremor.
- Cimetidine: Increases labetalol bioavailability and plasma levels.
- General anesthetics (e.g., halothane, isoflurane): Potentiation of hypotensive effects.
Moderate Interactions
Minor Interactions
- Not available
Monitoring
Baseline Monitoring
Blood Pressure (BP)
Rationale: To establish baseline and guide initial dosing.
Timing: Prior to first dose
Heart Rate (HR)
Rationale: To establish baseline and assess for bradycardia.
Timing: Prior to first dose
Electrocardiogram (ECG)
Rationale: To assess for pre-existing heart block or other arrhythmias.
Timing: Prior to first dose, especially in patients with cardiac history
Renal Function (BUN, Creatinine)
Rationale: To assess kidney function, as elimination is partly renal.
Timing: Prior to first dose
Liver Function Tests (ALT, AST, Bilirubin)
Rationale: To assess liver function, as labetalol is extensively metabolized by the liver.
Timing: Prior to first dose, especially in patients with hepatic impairment
Routine Monitoring
Blood Pressure (BP)
Frequency: Every 5-15 minutes during titration, then hourly or as clinically indicated once stable.
Target: Individualized, typically <140/90 mmHg or specific target for condition (e.g., 160/100 mmHg for hypertensive emergency).
Action Threshold: Hypotension (e.g., SBP <90 mmHg or symptomatic), or inadequate BP control.
Heart Rate (HR)
Frequency: Every 5-15 minutes during titration, then hourly or as clinically indicated once stable.
Target: Typically >50-60 bpm.
Action Threshold: Bradycardia (e.g., HR <50 bpm or symptomatic).
ECG Monitoring
Frequency: Continuous during IV infusion, especially during titration.
Target: Normal sinus rhythm, no significant conduction abnormalities.
Action Threshold: Development of AV block, severe bradycardia, or other arrhythmias.
Fluid Balance/Urine Output
Frequency: Hourly during acute management.
Target: Adequate urine output (>0.5 mL/kg/hr).
Action Threshold: Oliguria or anuria, signs of fluid overload.
Symptom Monitoring
- Dizziness
- Lightheadedness
- Fatigue
- Nausea
- Headache
- Orthostatic hypotension (especially when standing)
- Shortness of breath or wheezing (signs of bronchospasm)
- Signs of heart failure exacerbation (e.g., edema, dyspnea)
- Signs of liver injury (e.g., jaundice, dark urine, persistent nausea/vomiting)
Special Patient Groups
Pregnancy
Labetalol is often considered a first-line agent for the management of acute severe hypertension in pregnancy (e.g., preeclampsia with severe features, eclampsia). While classified as Category C (older system), its benefits in controlling severe hypertension in pregnancy generally outweigh potential risks to the fetus. Fetal growth restriction, bradycardia, and hypoglycemia have been reported, but are often associated with uncontrolled maternal hypertension or other factors.
Trimester-Specific Risks:
First Trimester:
Limited data, but generally avoided unless absolutely necessary due to potential for fetal exposure during organogenesis. However, acute use for severe hypertension is often emergent.
Second Trimester:
Commonly used for acute severe hypertension. Fetal monitoring for bradycardia and growth restriction is recommended.
Third Trimester:
Commonly used for acute severe hypertension. Neonatal bradycardia, hypoglycemia, and respiratory depression have been reported following maternal use near term, requiring close monitoring of the neonate.
Lactation
Labetalol is excreted into breast milk in small amounts. It is generally considered compatible with breastfeeding, and adverse effects in breastfed infants are rare. Monitor the infant for signs of beta-blockade (e.g., bradycardia, lethargy, poor feeding).
Infant Risk:
Low risk (L3)
Pediatric Use
Safety and efficacy in pediatric patients have not been established. Use is off-label and typically reserved for critical care settings for severe hypertension, with careful titration and monitoring. Dosing is weight-based and highly individualized.
Geriatric Use
Use with caution in elderly patients, as they may be more sensitive to the hypotensive and bradycardic effects. Start with lower doses and titrate slowly. Monitor for orthostatic hypotension and renal function.
Clinical Information
Clinical Pearls
- Labetalol IV is a preferred agent for hypertensive emergencies, especially in pregnancy, due to its relatively rapid onset and predictable effect.
- Administer IV boluses slowly (over 2 minutes) to minimize orthostatic hypotension.
- Patients should remain supine during and for at least 3 hours after IV administration to prevent orthostatic hypotension.
- Avoid in patients with asthma or severe COPD due to non-selective beta-blockade and risk of bronchospasm.
- Can cause scalp tingling, which is a common and benign side effect, usually transient.
- Monitor for signs of liver injury, though rare, as severe hepatocellular injury has been reported.
Alternative Therapies
- Nicardipine (calcium channel blocker, IV)
- Hydralazine (direct vasodilator, IV)
- Esmolol (selective beta-blocker, IV, very short-acting)
- Sodium Nitroprusside (direct vasodilator, IV, requires arterial line monitoring)
- Fenoldopam (dopamine-1 agonist, IV)
- Clevidipine (dihydropyridine calcium channel blocker, IV)
Cost & Coverage
Average Cost:
Varies, typically $10-$50 per 40ml vial (5mg/ml) per 40ml vial
Generic Available:
Yes
Insurance Coverage:
Tier 1 or 2 (Generic)
General Drug Facts
If your symptoms or health problems do not improve or worsen over time, it is essential to contact your doctor for further evaluation and guidance.
To ensure safe use, do not share your medication with others, and never take someone else's medication. Store all medications in a secure location, out of the reach of children and pets, to prevent accidental ingestion.
Proper disposal of unused or expired medications is crucial. Do not dispose of them by flushing them down the toilet or pouring them down the drain unless specifically instructed to do so. If you are unsure about the best method for disposing of your medication, consult your pharmacist for guidance. Many communities have drug take-back programs, which your pharmacist can help you locate.
Some medications may come with an additional patient information leaflet. Check with your pharmacist to see if this applies to your prescription. If you have any questions or concerns about your medication, do not hesitate to discuss them with your doctor, nurse, pharmacist, or other healthcare provider.
In the event of a suspected overdose, immediately contact your local poison control center or seek emergency medical attention. Be prepared to provide information about the medication taken, the amount, and the time it was taken, as this will aid in providing appropriate treatment.
To ensure safe use, do not share your medication with others, and never take someone else's medication. Store all medications in a secure location, out of the reach of children and pets, to prevent accidental ingestion.
Proper disposal of unused or expired medications is crucial. Do not dispose of them by flushing them down the toilet or pouring them down the drain unless specifically instructed to do so. If you are unsure about the best method for disposing of your medication, consult your pharmacist for guidance. Many communities have drug take-back programs, which your pharmacist can help you locate.
Some medications may come with an additional patient information leaflet. Check with your pharmacist to see if this applies to your prescription. If you have any questions or concerns about your medication, do not hesitate to discuss them with your doctor, nurse, pharmacist, or other healthcare provider.
In the event of a suspected overdose, immediately contact your local poison control center or seek emergency medical attention. Be prepared to provide information about the medication taken, the amount, and the time it was taken, as this will aid in providing appropriate treatment.