Ed A-Hist 4-10mg Tablets
It is used to treat nose stuffiness.It is used to ease allergy signs.
Drug Class
Antihistamine, Decongestant
Pharmacologic Class
H1-receptor antagonist (Chlorpheniramine), Alpha-1 adrenergic agonist (Phenylephrine)
Pregnancy Category
Category C
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
This medicine is a combination of an antihistamine and a decongestant. The antihistamine helps relieve sneezing, runny nose, and watery eyes caused by allergies or colds. The decongestant helps clear up stuffy nose by shrinking blood vessels in the nasal passages.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. You can take this medication with or without food. If it causes stomach upset, taking it with food may help.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of the reach of children and pets. When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so. Instead, consult your pharmacist for guidance on proper disposal. You may also have access to drug take-back programs in your area.
Missing a Dose
If you take this medication regularly and miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your normal schedule. Do not take two doses at the same time or extra doses. If you take this medication as needed, do not take it more frequently than directed by your doctor.
To use this medication correctly, follow your doctor's instructions and read all the information provided. You can take this medication with or without food. If it causes stomach upset, taking it with food may help.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of the reach of children and pets. When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so. Instead, consult your pharmacist for guidance on proper disposal. You may also have access to drug take-back programs in your area.
Missing a Dose
If you take this medication regularly and miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your normal schedule. Do not take two doses at the same time or extra doses. If you take this medication as needed, do not take it more frequently than directed by your doctor.
Lifestyle & Tips
- Avoid driving or operating heavy machinery until you know how this medication affects you, as it may cause drowsiness.
- Avoid alcohol and other sedatives, as they can increase drowsiness.
- Stay hydrated to help with dry mouth.
- Do not exceed the recommended dose.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
1 tablet every 4-6 hours as needed
Dose Range:
4 - 10 mg
Condition-Specific Dosing:
maximum_daily_dose:
Do not exceed 6 tablets in 24 hours
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established (generally not recommended for children under 2 years)
Child:
Not established (consult a physician for children under 12 years; specific pediatric formulations/doses may exist for single ingredients)
Adolescent:
1 tablet every 4-6 hours as needed (for ages 12 years and older)
Dose Adjustments
Renal Impairment:
Mild:
Use with caution; consider reduced frequency
Moderate:
Use with caution; consider reduced frequency
Severe:
Avoid or use with extreme caution; significant dose reduction likely needed due to chlorpheniramine excretion
Dialysis:
Not well studied; likely not dialyzable for chlorpheniramine; phenylephrine is not dialyzable
Hepatic Impairment:
Mild:
Use with caution
Moderate:
Use with caution; consider reduced frequency or dose due to metabolism of both components
Severe:
Avoid or use with extreme caution; significant dose reduction likely needed
Confidence:
Medium
Pharmacology
Mechanism of Action
Chlorpheniramine is an alkylamine antihistamine that competitively antagonizes H1-receptors, thereby preventing histamine from binding and reducing allergic symptoms like sneezing, runny nose, and watery eyes. Phenylephrine is a direct-acting sympathomimetic amine that acts primarily on alpha-1 adrenergic receptors in the respiratory tract mucosa, causing vasoconstriction and reducing nasal congestion.
Pharmacokinetics
Absorption:
Bioavailability:
Chlorpheniramine: 25-60%; Phenylephrine: Low oral bioavailability (due to first-pass metabolism)
Tmax:
Chlorpheniramine: 2.5-6 hours; Phenylephrine: 0.5-2 hours
FoodEffect:
Food may delay absorption but generally does not significantly affect extent of absorption.
Distribution:
Vd:
Chlorpheniramine: 1-10 L/kg; Phenylephrine: Not well established orally
ProteinBinding:
Chlorpheniramine: 69-72%; Phenylephrine: Not extensively protein bound
CnssPenetration:
Chlorpheniramine: Yes (causes sedation); Phenylephrine: Limited (does not readily cross BBB)
Elimination:
HalfLife:
Chlorpheniramine: 12-43 hours; Phenylephrine: 2-3 hours
Clearance:
Not readily available for combination
ExcretionRoute:
Renal (primarily for chlorpheniramine, metabolites for phenylephrine)
Unchanged:
Chlorpheniramine: 3-10% (urine); Phenylephrine: <1% (urine)
Pharmacodynamics
OnsetOfAction:
Chlorpheniramine: 15-60 minutes; Phenylephrine: 15-30 minutes
PeakEffect:
Chlorpheniramine: 2-6 hours; Phenylephrine: 1-2 hours
DurationOfAction:
Chlorpheniramine: 4-6 hours; Phenylephrine: 4-6 hours
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. Immediately contact your doctor or seek medical attention if you experience any of the following symptoms, which may indicate a serious allergic reaction:
- Rash
- Hives
- Itching
- Red, swollen, blistered, or peeling skin, with or without fever
- Wheezing
- Tightness in the chest or throat
- Difficulty breathing, swallowing, or talking
- Unusual hoarseness
- Swelling of the mouth, face, lips, tongue, or throat
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. Contact your doctor or seek medical help if you experience any of the following side effects or if they persist or bother you:
- Dizziness or drowsiness
- Feeling nervous or excitable
- Difficulty sleeping
Note: This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, consult your doctor. For medical advice 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.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. Immediately contact your doctor or seek medical attention if you experience any of the following symptoms, which may indicate a serious allergic reaction:
- Rash
- Hives
- Itching
- Red, swollen, blistered, or peeling skin, with or without fever
- Wheezing
- Tightness in the chest or throat
- Difficulty breathing, swallowing, or talking
- Unusual hoarseness
- Swelling of the mouth, face, lips, tongue, or throat
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. Contact your doctor or seek medical help if you experience any of the following side effects or if they persist or bother you:
- Dizziness or drowsiness
- Feeling nervous or excitable
- Difficulty sleeping
Note: This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, consult your doctor. For medical advice 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.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or drowsiness
- Fast or irregular heartbeat
- Difficulty urinating
- Vision changes
- Severe nervousness or anxiety
- Signs of an allergic reaction (rash, itching, swelling, severe dizziness, trouble breathing)
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 allergic reaction you experienced, including any symptoms that occurred.
If you have taken certain medications for depression or Parkinson's disease within the last 14 days, including isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline, as this may increase the risk of very high blood pressure.
If you are currently taking linezolid or methylene blue, as these medications can interact with this drug.
To ensure your safety, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter medications you are taking
Any natural products or vitamins you are using
Any health problems you have
This information will help your doctor determine whether it is safe for you to take this medication with your other medications and health conditions. Never start, stop, or change the dose 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 allergic reaction you experienced, including any symptoms that occurred.
If you have taken certain medications for depression or Parkinson's disease within the last 14 days, including isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline, as this may increase the risk of very high blood pressure.
If you are currently taking linezolid or methylene blue, as these medications can interact with this drug.
To ensure your safety, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter medications you are taking
Any natural products or vitamins you are using
Any health problems you have
This information will help your doctor determine whether it is safe for you to take this medication with your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
To minimize the risk of severe side effects, do not exceed the dosage prescribed by your doctor. Taking more than the recommended amount may increase your chance of experiencing severe side effects. Additionally, do not take this medication for a longer period than specified by your doctor.
Until you understand how this medication affects you, avoid operating a vehicle, performing tasks that require alertness, or engaging in activities that demand your full attention. It is also recommended to avoid consuming alcohol while taking this drug.
Before using marijuana, other forms of cannabis, or prescription and over-the-counter (OTC) medications that may cause drowsiness or slow your reactions, consult with your doctor.
When administering this medication to children, it is crucial to note that different brands may have varying dosage recommendations. Consult with your doctor before giving this medication to a child, as they require careful consideration. Children may have a higher risk of experiencing excitability, and this medication should not be used as a means to induce sleep. If you are considering giving this medication to a child, discuss the potential benefits and risks with your doctor.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. It is necessary to discuss the potential benefits and risks of this medication to both you and your baby to make an informed decision.
To minimize the risk of severe side effects, do not exceed the dosage prescribed by your doctor. Taking more than the recommended amount may increase your chance of experiencing severe side effects. Additionally, do not take this medication for a longer period than specified by your doctor.
Until you understand how this medication affects you, avoid operating a vehicle, performing tasks that require alertness, or engaging in activities that demand your full attention. It is also recommended to avoid consuming alcohol while taking this drug.
Before using marijuana, other forms of cannabis, or prescription and over-the-counter (OTC) medications that may cause drowsiness or slow your reactions, consult with your doctor.
When administering this medication to children, it is crucial to note that different brands may have varying dosage recommendations. Consult with your doctor before giving this medication to a child, as they require careful consideration. Children may have a higher risk of experiencing excitability, and this medication should not be used as a means to induce sleep. If you are considering giving this medication to a child, discuss the potential benefits and risks with your doctor.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. It is necessary to discuss the potential benefits and risks of this medication to both you and your baby to make an informed decision.
Overdose Information
Overdose Symptoms:
- Severe drowsiness or agitation
- Hallucinations
- Seizures
- Dilated pupils
- Flushing
- Fever
- Rapid heartbeat
- High blood pressure
- Urinary retention
- Coma
What to Do:
Call 911 or Poison Control immediately (1-800-222-1222). Seek emergency medical attention.
Drug Interactions
Contraindicated Interactions
- Monoamine Oxidase Inhibitors (MAOIs) (concurrent use or within 14 days of MAOI discontinuation) - risk of hypertensive crisis and severe anticholinergic effects
Major Interactions
- Other sympathomimetics (e.g., decongestants, appetite suppressants, amphetamines) - increased risk of cardiovascular effects
- Beta-blockers (non-selective) - may increase pressor response to phenylephrine
- Tricyclic antidepressants - may potentiate pressor effects of phenylephrine
- CNS depressants (e.g., alcohol, sedatives, hypnotics, anxiolytics, opioids) - increased sedation and CNS depression
- Anticholinergic drugs (e.g., atropine, tricyclic antidepressants, some antipsychotics) - increased anticholinergic side effects (dry mouth, urinary retention, blurred vision)
Moderate Interactions
- Digoxin - increased risk of arrhythmias with phenylephrine
- Ergot alkaloids - increased risk of vasoconstriction
- Antihypertensives - phenylephrine may reduce the effect of antihypertensive medications
Minor Interactions
- Not available
Monitoring
Baseline Monitoring
Blood Pressure
Rationale: Phenylephrine can increase blood pressure, especially in patients with pre-existing hypertension.
Timing: Before initiating therapy in patients with cardiovascular risk factors.
Medical History (especially cardiovascular, thyroid, prostate, glaucoma)
Rationale: Identify contraindications or precautions.
Timing: Before initiating therapy.
Routine Monitoring
Symptom relief
Frequency: Daily, as needed
Target: Reduction in sneezing, runny nose, nasal congestion
Action Threshold: Lack of efficacy or worsening symptoms may indicate need for alternative therapy or medical evaluation.
Adverse effects (e.g., sedation, dizziness, dry mouth, urinary retention, palpitations)
Frequency: Daily, as needed
Target: Absence or mild, tolerable effects
Action Threshold: Severe or persistent adverse effects warrant discontinuation and medical advice.
Symptom Monitoring
- Drowsiness
- Dizziness
- Dry mouth
- Blurred vision
- Urinary retention
- Nervousness
- Insomnia
- Palpitations
- Increased blood pressure
Special Patient Groups
Pregnancy
Generally not recommended unless clearly needed and benefits outweigh risks. Both chlorpheniramine and phenylephrine are Category C. Consult a healthcare provider.
Trimester-Specific Risks:
First Trimester:
Limited data; avoid if possible.
Second Trimester:
Use with caution; generally considered safer than first trimester, but still consult physician.
Third Trimester:
Avoid close to term due to potential for adverse effects on fetus (e.g., premature closure of ductus arteriosus with sympathomimetics, although less likely with phenylephrine than pseudoephedrine) and increased risk of maternal side effects.
Lactation
Use with caution. Both chlorpheniramine and phenylephrine are excreted in breast milk. Chlorpheniramine can cause drowsiness in the infant and may decrease milk supply. Phenylephrine may also decrease milk supply. L3 risk.
Infant Risk:
Irritability, drowsiness, decreased feeding (chlorpheniramine); potential for decreased milk supply (both).
Pediatric Use
Not recommended for children under 12 years of age without consulting a physician. Over-the-counter cough and cold products are generally not recommended for children under 2 years due to potential for serious side effects. Dosing for older children should be based on weight and age, and specific pediatric formulations are preferred.
Geriatric Use
Use with caution. Elderly patients are more susceptible to anticholinergic effects (e.g., sedation, confusion, urinary retention, constipation) and sympathomimetic effects (e.g., increased blood pressure, palpitations, insomnia). Start with lower doses and monitor closely.
Clinical Information
Clinical Pearls
- Advise patients to avoid concurrent use with other cold/flu medications to prevent accidental overdose of active ingredients.
- Warn patients about potential for drowsiness and impaired ability to perform tasks requiring mental alertness.
- Counsel patients with pre-existing conditions like hypertension, heart disease, thyroid disorders, glaucoma, or prostate enlargement to consult a doctor before use.
- This combination is for symptomatic relief and does not treat the underlying cause of cold or allergy.
Alternative Therapies
- Single-ingredient antihistamines (e.g., loratadine, cetirizine for non-drowsy options; diphenhydramine for drowsy)
- Single-ingredient decongestants (e.g., pseudoephedrine, oxymetazoline nasal spray)
- Nasal saline sprays
- Nasal corticosteroids (for allergic rhinitis)
- Oral analgesics/antipyretics (for fever/pain)
Cost & Coverage
Average Cost:
$5 - $20 per 30 tablets
Generic Available:
Yes
Insurance Coverage:
OTC (generally not covered by prescription plans, but may be eligible for FSA/HSA)
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 your medication, don't hesitate to reach out to 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.