Banophen (diphenhydramine) 50mg CP
It is used to ease allergy signs.
Drug Class
Antihistamine, Sedative/Hypnotic, Antitussive, Antiemetic
Pharmacologic Class
First-generation H1-receptor antagonist, Anticholinergic
Pregnancy Category
Category B
FDA Approved
Mar 1946
DEA Schedule
Not Controlled
Overview
What is this medicine?
Diphenhydramine is an antihistamine used to relieve allergy symptoms like sneezing, runny nose, and itchy eyes. It can also be used to help you fall asleep because it causes drowsiness. It's also found in some cough and cold medicines.
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, but if it causes stomach upset, take it with food.
Storing and Disposing of Your Medication
Store this medication at room temperature, away from light and moisture. Keep it in a dry place, such as a closet or drawer, and avoid storing it in the bathroom. Keep all medications in a safe location, 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, check with your pharmacist for guidance on proper disposal or participate in a drug take-back program 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 regular schedule. Do not take two doses at the same time or take 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, but if it causes stomach upset, take it with food.
Storing and Disposing of Your Medication
Store this medication at room temperature, away from light and moisture. Keep it in a dry place, such as a closet or drawer, and avoid storing it in the bathroom. Keep all medications in a safe location, 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, check with your pharmacist for guidance on proper disposal or participate in a drug take-back program 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 regular schedule. Do not take two doses at the same time or take 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 can cause significant drowsiness.
- Avoid alcohol and other sedatives while taking this medication, as they can increase drowsiness.
- Take with food or milk if stomach upset occurs.
- Do not exceed the recommended dose.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
For sleep: 50 mg orally at bedtime. For allergy/cold symptoms: 25-50 mg orally every 4-6 hours.
Dose Range:
25 - 50 mg
Condition-Specific Dosing:
Maximum daily dose:
300 mg
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established (generally not recommended for infants)
Child:
6 to <12 years: 12.5-25 mg orally every 4-6 hours (max 150 mg/day). Not recommended for children under 6 years for cough/cold.
Adolescent:
âĨ12 years: 25-50 mg orally every 4-6 hours (max 300 mg/day).
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment needed.
Moderate:
Consider dose reduction (e.g., 25 mg every 6-8 hours) if CrCl < 50 mL/min.
Severe:
Significant dose reduction recommended (e.g., 25 mg every 8-12 hours) if CrCl < 10 mL/min.
Dialysis:
Diphenhydramine is not significantly removed by dialysis. Administer after dialysis on dialysis days. Monitor for increased side effects.
Hepatic Impairment:
Mild:
No specific adjustment needed.
Moderate:
Consider dose reduction.
Severe:
Significant dose reduction recommended due to extensive hepatic metabolism. Monitor for increased side effects.
Pharmacology
Mechanism of Action
Diphenhydramine is a first-generation antihistamine that competitively antagonizes H1-receptors in the periphery and CNS, leading to sedative, anticholinergic, antiemetic, and antitussive effects. Its sedative properties are due to its ability to cross the blood-brain barrier and block H1 receptors in the brain. Anticholinergic effects are due to its antagonism of muscarinic acetylcholine receptors.
Pharmacokinetics
Absorption:
Bioavailability:
40-60% (due to first-pass metabolism)
Tmax:
1-4 hours
FoodEffect:
Food may slightly delay absorption but does not significantly affect bioavailability.
Distribution:
Vd:
17 L/kg (wide distribution)
ProteinBinding:
78-85%
CnssPenetration:
Yes
Elimination:
HalfLife:
2.4-9.3 hours (average 4-8 hours)
Clearance:
Not available (highly variable)
ExcretionRoute:
Renal (primarily as metabolites)
Unchanged:
<1% (in urine)
Pharmacodynamics
OnsetOfAction:
15-60 minutes
PeakEffect:
1-4 hours
DurationOfAction:
4-6 hours
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
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
Changes in balance
Feeling less alert than usual
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only mild ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or persist, contact your doctor for guidance:
Dizziness or drowsiness
Thickening of mucus in the nose or throat
Feeling nervous or excitable
Upset stomach or vomiting
This list is not exhaustive, and you may experience other side effects not mentioned here. 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.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
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
Changes in balance
Feeling less alert than usual
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only mild ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or persist, contact your doctor for guidance:
Dizziness or drowsiness
Thickening of mucus in the nose or throat
Feeling nervous or excitable
Upset stomach or vomiting
This list is not exhaustive, and you may experience other side effects not mentioned here. 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 drowsiness or dizziness
- Confusion or disorientation
- Difficulty urinating or inability to urinate
- Blurred vision or dry eyes
- Severe dry mouth
- Fast or irregular heartbeat
- 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. Be sure to describe the allergic reaction and its symptoms.
If you are breastfeeding or plan to breastfeed, as you may need to avoid breastfeeding while taking this medication.
If the patient is a premature baby or newborn, as this form of the medication should not be given to them.
This is not an exhaustive list of all potential interactions with this medication. Therefore, it is crucial to discuss the following with your doctor and pharmacist:
All medications you are currently taking, including prescription and over-the-counter drugs, natural products, and vitamins.
* Any health problems you have, as they may interact with this medication.
To ensure your safety, do not start, stop, or change the dose of any medication without first consulting your doctor. It is vital to verify that it is safe to take this medication with all your other medications and health conditions.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction and its symptoms.
If you are breastfeeding or plan to breastfeed, as you may need to avoid breastfeeding while taking this medication.
If the patient is a premature baby or newborn, as this form of the medication should not be given to them.
This is not an exhaustive list of all potential interactions with this medication. Therefore, it is crucial to discuss the following with your doctor and pharmacist:
All medications you are currently taking, including prescription and over-the-counter drugs, natural products, and vitamins.
* Any health problems you have, as they may interact with this medication.
To ensure your safety, do not start, stop, or change the dose of any medication without first consulting your doctor. It is vital to verify that it is safe to take this medication with all your other medications and health conditions.
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, adhere strictly to the dosage instructions provided by your doctor. Do not exceed the recommended dose, as this may increase your chance of experiencing severe side effects. Additionally, do not take this medication for a longer duration than prescribed by your doctor.
Until you are familiar with how this medication affects you, avoid operating a vehicle or engaging in any activities that require alertness.
Do not use this medication in conjunction with other products that contain diphenhydramine. It is also recommended to avoid consuming alcohol while taking this drug, as it may exacerbate side effects.
Before using marijuana, other forms of cannabis, or any prescription or over-the-counter (OTC) medications that may cause drowsiness, consult with your doctor to discuss potential interactions.
It is crucial to note that different brands of this medication may be suitable for children of various ages. Therefore, consult with your doctor before administering this medication to a child. Furthermore, do not use this medication as a means to induce sleep in children; instead, consult with your doctor for appropriate guidance.
If you are 60 years or older, exercise caution when using this medication, as you may be more susceptible to side effects. Similarly, when administering this medication to children, use it with caution, as they may have a higher risk of experiencing excitability.
If you are pregnant or planning to become pregnant, inform your doctor, as it is necessary to discuss the benefits and risks associated with using this medication during pregnancy.
To minimize the risk of severe side effects, adhere strictly to the dosage instructions provided by your doctor. Do not exceed the recommended dose, as this may increase your chance of experiencing severe side effects. Additionally, do not take this medication for a longer duration than prescribed by your doctor.
Until you are familiar with how this medication affects you, avoid operating a vehicle or engaging in any activities that require alertness.
Do not use this medication in conjunction with other products that contain diphenhydramine. It is also recommended to avoid consuming alcohol while taking this drug, as it may exacerbate side effects.
Before using marijuana, other forms of cannabis, or any prescription or over-the-counter (OTC) medications that may cause drowsiness, consult with your doctor to discuss potential interactions.
It is crucial to note that different brands of this medication may be suitable for children of various ages. Therefore, consult with your doctor before administering this medication to a child. Furthermore, do not use this medication as a means to induce sleep in children; instead, consult with your doctor for appropriate guidance.
If you are 60 years or older, exercise caution when using this medication, as you may be more susceptible to side effects. Similarly, when administering this medication to children, use it with caution, as they may have a higher risk of experiencing excitability.
If you are pregnant or planning to become pregnant, inform your doctor, as it is necessary to discuss the benefits and risks associated with using this medication during pregnancy.
Overdose Information
Overdose Symptoms:
- Severe drowsiness or deep sleep
- Excitement, agitation, or hallucinations (especially in children)
- Dilated pupils
- Flushed skin
- Dry mouth and skin
- Urinary retention
- Rapid heartbeat
- Seizures
- Coma
What to Do:
Seek immediate medical attention. Call 911 or Poison Control at 1-800-222-1222. Treatment is supportive and symptomatic.
Drug Interactions
Major Interactions
- CNS depressants (e.g., alcohol, opioids, benzodiazepines, sedatives, hypnotics): Increased sedation and respiratory depression.
- Anticholinergic drugs (e.g., tricyclic antidepressants, atropine, some antipsychotics): Increased risk of anticholinergic side effects (dry mouth, blurred vision, urinary retention, constipation).
Moderate Interactions
- Monoamine Oxidase Inhibitors (MAOIs): May prolong and intensify the anticholinergic and CNS depressant effects of diphenhydramine. Avoid concomitant use or use with extreme caution.
- Potassium chloride (oral): Increased risk of severe gastrointestinal lesions due to anticholinergic-induced delayed gastric emptying.
Minor Interactions
- Betahistine: Diphenhydramine may reduce the effect of betahistine (H1-receptor agonist).
Monitoring
Symptom Monitoring
- Level of sedation/drowsiness
- Anticholinergic symptoms (dry mouth, blurred vision, urinary retention, constipation)
- Paradoxical excitation (especially in children)
- Effectiveness for intended use (allergy relief, sleep)
Special Patient Groups
Pregnancy
Generally considered safe for occasional use during pregnancy (Category B), particularly in the first and second trimesters. However, caution is advised, especially in the third trimester, due to potential for uterine contractions or neonatal withdrawal symptoms (e.g., irritability, tremors) if used chronically.
Trimester-Specific Risks:
First Trimester:
Low risk, generally considered compatible.
Second Trimester:
Low risk, generally considered compatible.
Third Trimester:
Potential for neonatal withdrawal symptoms or uterine contractions with chronic use. Use with caution.
Lactation
Excreted into breast milk (L3 - Moderately Safe). May cause drowsiness or irritability in the infant and may decrease milk supply, especially with regular use or in combination with pseudoephedrine. Use with caution, observe infant for sedation.
Infant Risk:
Low to moderate risk of sedation, irritability, or decreased milk supply.
Pediatric Use
Not recommended for children under 6 years for cough/cold symptoms. Use with caution in children due to potential for paradoxical excitation (hyperactivity, agitation) rather than sedation. Dosing must be weight-based for younger children.
Geriatric Use
Increased sensitivity to anticholinergic effects (e.g., confusion, urinary retention, constipation, dry mouth, blurred vision) and sedative effects. Increased risk of falls. Use lowest effective dose and avoid chronic use. Often listed on Beers Criteria as a medication to avoid in older adults due to high anticholinergic burden.
Clinical Information
Clinical Pearls
- Diphenhydramine is a first-generation antihistamine known for its significant sedative and anticholinergic side effects.
- It is commonly used as an OTC sleep aid due to its sedative properties.
- Avoid in elderly patients due to high anticholinergic burden and increased risk of falls, cognitive impairment, and urinary retention.
- Paradoxical excitation (agitation, hyperactivity) can occur, especially in young children.
- Tolerance to the sedative effect can develop with chronic use, making it less effective as a sleep aid over time.
- Patients should be advised about potential for impaired driving or operating machinery.
Alternative Therapies
- Second-generation antihistamines (e.g., loratadine, cetirizine, fexofenadine) for allergy relief with less sedation.
- Non-pharmacological sleep aids (e.g., sleep hygiene, CBT-I) for insomnia.
- Other OTC sleep aids (e.g., doxylamine).
- Prescription hypnotics (e.g., zolpidem, eszopiclone) for insomnia (different mechanism, higher risk profile).
Cost & Coverage
Average Cost:
Low cost per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Typically covered as a generic, often Tier 1 or OTC.
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure safe and effective treatment, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it's a good idea to check with your pharmacist for more information. If you have any questions or concerns about your 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 emergency medical attention. When reporting the incident, be prepared to provide details about the medication taken, the amount, and the time it occurred.