Phenylephrine 10mg/ml Inj, 10ml
It is used to treat low blood pressure.
Drug Class
Vasopressor
Pharmacologic Class
Alpha-1 adrenergic agonist
Pregnancy Category
Category C
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
Phenylephrine is a medicine given by injection, usually into a vein, to help raise blood pressure when it drops too low, such as during surgery or in certain medical emergencies. It works by tightening blood vessels.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided to you. It is essential to follow the instructions carefully. This medication is administered via injection into a vein, either as a single dose or continuously over a period of time.
Storing and Disposing of Your Medication
If you need to store this medication at home, consult with your doctor, nurse, or pharmacist to determine the proper storage procedure.
Missing a Dose
If you miss a dose, contact your doctor to receive guidance on what to do next.
To use this medication correctly, follow your doctor's instructions and read all the information provided to you. It is essential to follow the instructions carefully. This medication is administered via injection into a vein, either as a single dose or continuously over a period of time.
Storing and Disposing of Your Medication
If you need to store this medication at home, consult with your doctor, nurse, or pharmacist to determine the proper storage procedure.
Missing a Dose
If you miss a dose, contact your doctor to receive guidance on what to do next.
Lifestyle & Tips
- This medication is typically administered in a hospital or clinical setting under close medical supervision.
- Patients should report any discomfort at the injection site, or symptoms like headache, dizziness, or chest pain immediately to their healthcare provider.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
Initial bolus: 0.1-0.5 mg IV, may repeat every 10-15 minutes as needed. Continuous infusion: 10-200 mcg/min, titrated to blood pressure response.
Dose Range:
0.1 - 0.5 mg
Condition-Specific Dosing:
hypotension_during_anesthesia:
Initial bolus: 0.05-0.2 mg IV. Continuous infusion: 0.5-1 mcg/kg/min.
shock:
Continuous infusion: 10-200 mcg/min, titrated to maintain target blood pressure.
Pediatric Dosing
Neonatal:
Not established (use with extreme caution, often 0.5-1 mcg/kg/min IV infusion, titrated)
Infant:
Not established (use with extreme caution, often 0.5-1 mcg/kg/min IV infusion, titrated)
Child:
Not established (use with extreme caution, often 0.5-1 mcg/kg/min IV infusion, titrated)
Adolescent:
Similar to adult dosing, but start with lower doses and titrate carefully.
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment recommended, monitor closely.
Moderate:
No specific adjustment recommended, monitor closely.
Severe:
No specific adjustment recommended, monitor closely, consider lower initial doses.
Dialysis:
Not significantly dialyzable. Monitor closely, adjust dose based on response.
Hepatic Impairment:
Mild:
No specific adjustment recommended, monitor closely.
Moderate:
No specific adjustment recommended, monitor closely.
Severe:
No specific adjustment recommended, monitor closely, consider lower initial doses due to primary metabolism in liver.
Pharmacology
Mechanism of Action
Phenylephrine is a direct-acting sympathomimetic amine that acts almost exclusively on alpha-1 adrenergic receptors, causing potent vasoconstriction in arterioles and venules. This leads to an increase in systemic vascular resistance (SVR), mean arterial pressure (MAP), and often a reflex bradycardia. It has minimal beta-adrenergic activity.
Pharmacokinetics
Absorption:
Bioavailability:
100% (IV)
Tmax:
Immediate (IV)
FoodEffect:
Not applicable (IV)
Distribution:
Vd:
Approximately 340 L
ProteinBinding:
Low
CnssPenetration:
Limited
Elimination:
HalfLife:
Approximately 2.5 hours (IV)
Clearance:
Not readily available (highly metabolized)
ExcretionRoute:
Renal (primarily as inactive metabolites)
Unchanged:
< 16% (IV)
Pharmacodynamics
OnsetOfAction:
Immediate (IV)
PeakEffect:
1-2 minutes (IV bolus)
DurationOfAction:
15-20 minutes (IV bolus), dependent on infusion rate for continuous infusion
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Attention Immediately
Although rare, this medication can cause severe and potentially life-threatening side effects. If you experience 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
Signs of high blood pressure, including:
+ Severe headache
+ Dizziness
+ Fainting
+ Changes in vision
Chest pain or pressure
Shakiness
Signs of kidney problems, such as:
+ Inability to urinate
+ Changes in urine output
+ Blood in the urine
+ Sudden weight gain
Abnormal heart rhythms, including:
+ Fast heartbeat
+ Slow heartbeat
+ Irregular heartbeat
Blurred vision
Shortness of breath
Sudden weight gain
Swelling in the arms or legs
Numbness or tingling in the hands or feet
If you experience any of these symptoms, it is essential to seek medical attention immediately.
Additional Side Effects:
This medication can cause other side effects, which may be mild or severe. If you experience any of the following symptoms, contact your doctor or seek medical help if they bother you or do not go away:
Dizziness
Headache
Feeling nervous or excitable
Trouble sleeping
Restlessness
Upset stomach or vomiting
Excessive sweating
Stomach pain
Neck pain
Reporting Side Effects:
If you have any questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Important Note:
If you receive this medication through a vein, it can cause tissue damage if it leaks. Inform your nurse immediately if you experience any redness, burning, pain, swelling, blisters, skin sores, or fluid leakage at the injection site.
Although rare, this medication can cause severe and potentially life-threatening side effects. If you experience 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
Signs of high blood pressure, including:
+ Severe headache
+ Dizziness
+ Fainting
+ Changes in vision
Chest pain or pressure
Shakiness
Signs of kidney problems, such as:
+ Inability to urinate
+ Changes in urine output
+ Blood in the urine
+ Sudden weight gain
Abnormal heart rhythms, including:
+ Fast heartbeat
+ Slow heartbeat
+ Irregular heartbeat
Blurred vision
Shortness of breath
Sudden weight gain
Swelling in the arms or legs
Numbness or tingling in the hands or feet
If you experience any of these symptoms, it is essential to seek medical attention immediately.
Additional Side Effects:
This medication can cause other side effects, which may be mild or severe. If you experience any of the following symptoms, contact your doctor or seek medical help if they bother you or do not go away:
Dizziness
Headache
Feeling nervous or excitable
Trouble sleeping
Restlessness
Upset stomach or vomiting
Excessive sweating
Stomach pain
Neck pain
Reporting Side Effects:
If you have any questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Important Note:
If you receive this medication through a vein, it can cause tissue damage if it leaks. Inform your nurse immediately if you experience any redness, burning, pain, swelling, blisters, skin sores, or fluid leakage at the injection site.
Seek Immediate Medical Attention If You Experience:
- Severe headache
- Chest pain or tightness
- Irregular heartbeat (palpitations)
- Difficulty breathing
- Sudden weakness or numbness
- Vision changes
- Pain, swelling, or discoloration at the injection site (signs of extravasation)
Before Using This Medicine
Before taking this medication, it is essential to inform your doctor about the following:
Any allergies you have, including allergies to this drug, its components, or other substances, such as foods or medications. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have high blood pressure, as this medication may affect your condition.
If you have taken certain medications for depression or Parkinson's disease within the last 14 days, including isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline. Combining these medications with this drug can lead to severely high blood pressure.
If you are currently taking linezolid or methylene blue, as these medications can interact with this drug.
It is crucial to provide your doctor and pharmacist with a comprehensive list of all your medications, including prescription and over-the-counter drugs, natural products, and vitamins. This will help ensure that it is safe to take this medication with your other medications and health conditions. Do not start, stop, or change the dose of any medication without first consulting your doctor to confirm that it is safe to do so.
Any allergies you have, including allergies to this drug, its components, or other substances, such as foods or medications. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have high blood pressure, as this medication may affect your condition.
If you have taken certain medications for depression or Parkinson's disease within the last 14 days, including isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline. Combining these medications with this drug can lead to severely high blood pressure.
If you are currently taking linezolid or methylene blue, as these medications can interact with this drug.
It is crucial to provide your doctor and pharmacist with a comprehensive list of all your medications, including prescription and over-the-counter drugs, natural products, and vitamins. This will help ensure that it is safe to take this medication with your other medications and health conditions. Do not start, stop, or change the dose of any medication without first consulting your doctor to confirm that it is safe to do so.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. If you have a known allergy to sulfites, consult with your doctor, as some formulations of this drug may contain sulfites. Regular blood tests will be necessary, as directed by your doctor, to monitor your condition. Additionally, if you are pregnant, planning to become pregnant, or are breastfeeding, discuss the potential benefits and risks of this medication with your doctor to determine the best course of action for you and your baby.
Overdose Information
Overdose Symptoms:
- Severe hypertension (dangerously high blood pressure)
- Reflex bradycardia (very slow heart rate)
- Ventricular arrhythmias
- Cerebral hemorrhage
- Pulmonary edema
- Cardiac arrest
What to Do:
Treatment is symptomatic and supportive. Alpha-adrenergic blocking agents (e.g., phentolamine) may be used to counteract severe hypertension. Bradycardia may be treated with atropine. Call 1-800-222-1222 (Poison Control) or seek immediate medical attention.
Drug Interactions
Contraindicated Interactions
- Monoamine Oxidase Inhibitors (MAOIs) (concurrent use or within 14 days of MAOI discontinuation due to risk of hypertensive crisis)
Major Interactions
- Tricyclic Antidepressants (TCAs) (potentiate pressor effect)
- Atropine (potentiates pressor effect)
- Oxytocin and other oxytocic drugs (may cause severe persistent hypertension)
- Other vasopressors (additive pressor effects)
- Beta-adrenergic blockers (may lead to unopposed alpha-adrenergic effects and severe hypertension)
- General anesthetics (e.g., halothane, cyclopropane) (may sensitize myocardium to arrhythmias)
Moderate Interactions
- Digoxin (increased risk of arrhythmias)
- Alpha-adrenergic blockers (may reduce pressor effect of phenylephrine)
- Ergot alkaloids (additive vasoconstriction)
Minor Interactions
- Not readily available
Monitoring
Baseline Monitoring
Blood Pressure (BP)
Rationale: To establish baseline and guide initial dosing.
Timing: Prior to initiation of therapy
Heart Rate (HR)
Rationale: To establish baseline and monitor for reflex bradycardia.
Timing: Prior to initiation of therapy
Electrocardiogram (ECG)
Rationale: To assess cardiac rhythm and identify pre-existing abnormalities.
Timing: Prior to initiation of therapy, especially in patients with cardiac history
Peripheral Perfusion (e.g., capillary refill, skin color, temperature)
Rationale: To assess baseline tissue perfusion.
Timing: Prior to initiation of therapy
Routine Monitoring
Blood Pressure (BP)
Frequency: Continuously (arterial line preferred) or every 1-5 minutes during titration, then every 5-15 minutes once stable.
Target: Titrate to desired MAP or systolic BP as per clinical indication.
Action Threshold: Hypotension or hypertension outside target range; adjust infusion rate.
Heart Rate (HR)
Frequency: Continuously or every 1-5 minutes during titration, then every 5-15 minutes once stable.
Target: Maintain within physiological limits, monitor for significant bradycardia.
Action Threshold: Significant bradycardia (e.g., <50 bpm) or tachycardia; consider dose adjustment or atropine.
Electrocardiogram (ECG)
Frequency: Continuous cardiac monitoring.
Target: Normal sinus rhythm, absence of significant arrhythmias.
Action Threshold: Development of new arrhythmias (e.g., PVCs, bradycardia); investigate cause, adjust dose.
Urine Output
Frequency: Hourly
Target: >0.5 mL/kg/hr
Action Threshold: Oliguria or anuria; assess renal perfusion, fluid status, and consider alternative vasopressors.
Peripheral Perfusion (e.g., capillary refill, skin color, temperature, mental status)
Frequency: Every 1-4 hours or as clinically indicated.
Target: Warm, dry skin; brisk capillary refill; alert mental status.
Action Threshold: Signs of hypoperfusion (e.g., mottled skin, prolonged capillary refill, altered mental status); assess fluid status, consider dose adjustment or alternative vasopressors.
IV Site
Frequency: Regularly (e.g., every 1-2 hours)
Target: No signs of extravasation (swelling, pain, pallor).
Action Threshold: Signs of extravasation; stop infusion, infiltrate with phentolamine.
Symptom Monitoring
- Headache
- Palpitations
- Nausea
- Vomiting
- Anxiety
- Restlessness
- Tremor
- Dizziness
- Piloerection (goosebumps)
- Cold extremities
- Chest pain
- Shortness of breath
Special Patient Groups
Pregnancy
Category C. Use only if the potential benefit justifies the potential risk to the fetus. Phenylephrine can cause uterine vasoconstriction and reduce placental perfusion, potentially leading to fetal hypoxia and bradycardia.
Trimester-Specific Risks:
First Trimester:
Limited data, but potential for fetal harm due to vasoconstriction.
Second Trimester:
Potential for reduced placental perfusion and fetal hypoxia.
Third Trimester:
Potential for reduced placental perfusion, fetal hypoxia, and may cause severe persistent maternal hypertension when used with oxytocic drugs.
Lactation
L3 (Moderately safe). Phenylephrine is excreted into breast milk. However, oral bioavailability in the infant is poor, limiting systemic exposure. Monitor breastfed infant for signs of irritability, changes in feeding, or sleep patterns.
Infant Risk:
Low to moderate. Potential for irritability or mild cardiovascular effects in the infant, though unlikely due to poor oral absorption.
Pediatric Use
Use with extreme caution. Dosing is not well-established and is typically weight-based. Children may be more sensitive to the effects of vasopressors. Close hemodynamic monitoring is essential.
Geriatric Use
Use with caution. Elderly patients may be more sensitive to the pressor effects of phenylephrine and may have pre-existing cardiovascular conditions that increase the risk of adverse effects (e.g., hypertension, coronary artery disease, arrhythmias). Start with lower doses and titrate slowly.
Clinical Information
Clinical Pearls
- Phenylephrine is a pure alpha-1 agonist, making it useful when increased systemic vascular resistance is desired without significant chronotropic or inotropic effects (unlike norepinephrine or epinephrine).
- Risk of reflex bradycardia is common due to the significant increase in blood pressure. This can be managed with atropine if clinically significant.
- Extravasation is a serious complication that can lead to tissue necrosis. Administer via a central venous line if possible. If extravasation occurs, infiltrate the area with phentolamine (an alpha-adrenergic blocker) as soon as possible.
- Avoid abrupt discontinuation of continuous infusions, as this can lead to rebound hypotension.
- Careful titration is crucial, especially in patients with pre-existing cardiovascular disease, hyperthyroidism, or diabetes.
Alternative Therapies
- Norepinephrine (Levophed) - mixed alpha and beta agonist, often preferred for septic shock.
- Dopamine - dose-dependent effects (dopaminergic, beta, alpha).
- Epinephrine (Adrenalin) - mixed alpha and beta agonist, strong inotropic and chronotropic effects.
- Vasopressin (Vasostrict) - non-adrenergic vasopressor, often used as an adjunct in refractory shock.
- Angiotensin II (Giapreza) - for vasoplegic shock.
Cost & Coverage
Average Cost:
Varies widely by supplier and volume per 10ml vial
Generic Available:
Yes
Insurance Coverage:
Tier 1 or 2 (Generic)
General Drug Facts
If your symptoms or health problems persist or worsen, it is essential to contact your doctor promptly. To ensure safe use, never share your medication with others, and do not take medication prescribed for someone else. Store all medications in a secure location, out of reach of children and pets, to prevent accidental ingestion. Dispose of unused or expired medications properly. Unless instructed to do so by a healthcare professional, avoid flushing medications down the toilet or pouring them down the drain. If you are unsure about the correct disposal method, consult your pharmacist for guidance. Many communities offer 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, 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 occurred, as this will aid in providing appropriate treatment.