Panadol PM 25-500mg Tablets
It is used to treat sleep problems.It is used to ease pain and fever.
Drug Class
Analgesic, Antihistamine, Sleep Aid
Pharmacologic Class
Para-aminophenol derivative (Acetaminophen), Ethanolamine antihistamine (Diphenhydramine)
Pregnancy Category
Category B
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
Panadol PM is a combination medicine that contains acetaminophen for pain relief and diphenhydramine for sleep. It helps to relieve minor aches and pains that may keep you awake at night, and also helps you fall asleep.
How to Use This Medicine
Taking Your Medication
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. You can take this medication with or without food, but if it upsets your stomach, take it with food. It's recommended to take this medication at bedtime.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, avoiding the bathroom. Protect it from heat and keep it out of reach of children and pets. When you're finished with your medication or it's expired, dispose of it properly. Do not flush it down the toilet or pour it down the drain unless instructed to do so by your pharmacist. If you're unsure about how to dispose of your medication, ask your pharmacist for guidance. You may also want to check if there are any 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 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 get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. You can take this medication with or without food, but if it upsets your stomach, take it with food. It's recommended to take this medication at bedtime.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, avoiding the bathroom. Protect it from heat and keep it out of reach of children and pets. When you're finished with your medication or it's expired, dispose of it properly. Do not flush it down the toilet or pour it down the drain unless instructed to do so by your pharmacist. If you're unsure about how to dispose of your medication, ask your pharmacist for guidance. You may also want to check if there are any 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 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
- Do not take with alcohol or other sedatives, as this can increase drowsiness and the risk of serious side effects.
- Avoid driving or operating heavy machinery after taking this medication, as it can cause significant drowsiness.
- Do not take with other acetaminophen-containing products to avoid accidental overdose.
- Do not take with other antihistamines or sleep aids.
- Limit caffeine intake, as it can counteract the sedative effects.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
2 tablets (500mg Acetaminophen / 25mg Diphenhydramine per tablet) orally at bedtime
Condition-Specific Dosing:
maximum_daily_dose:
Do not take more than 2 tablets in 24 hours. Do not use for more than 10 days for pain or 2 weeks for insomnia without consulting a doctor.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not recommended for children under 12 years of age for sleep aid. For pain, consult a doctor for appropriate acetaminophen dosing.
Adolescent:
12 years and older: 2 tablets orally at bedtime.
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment typically required for short-term use, but monitor for accumulation of diphenhydramine.
Moderate:
Use with caution. Consider extended dosing intervals for diphenhydramine. Acetaminophen generally safe at standard doses.
Severe:
Use with caution. Consider extended dosing intervals for diphenhydramine. Acetaminophen may require dose reduction or extended intervals.
Dialysis:
Acetaminophen is dialyzable. Diphenhydramine is not significantly dialyzable. Use with caution and monitor for adverse effects.
Hepatic Impairment:
Mild:
Use with caution. Acetaminophen dose reduction may be necessary.
Moderate:
Use with caution. Acetaminophen dose reduction or avoidance may be necessary. Diphenhydramine metabolism may be impaired.
Severe:
Contraindicated due to acetaminophen component. Diphenhydramine should be avoided or used with extreme caution at reduced doses.
Confidence:
Medium
Pharmacology
Mechanism of Action
Acetaminophen: Produces analgesia by elevation of the pain threshold, likely through inhibition of prostaglandin synthesis in the central nervous system. It also acts as an antipyretic through a central effect on the hypothalamic heat-regulating center. Diphenhydramine: An antihistamine with anticholinergic (drying) and sedative properties. It competitively blocks H1 histamine receptors, leading to sedation and anticholinergic effects.
Pharmacokinetics
Absorption:
Bioavailability:
Acetaminophen: 60-90%; Diphenhydramine: 40-60% (due to first-pass metabolism)
Tmax:
Acetaminophen: 0.5-2 hours; Diphenhydramine: 1-4 hours
FoodEffect:
Food may slightly delay absorption of acetaminophen but does not significantly affect extent of absorption. Food may slightly delay Tmax for diphenhydramine.
Distribution:
Vd:
Acetaminophen: 0.95 L/kg; Diphenhydramine: 17 L/kg
ProteinBinding:
Acetaminophen: 10-25%; Diphenhydramine: 78-99%
CnssPenetration:
Acetaminophen: Yes (limited); Diphenhydramine: Yes (readily crosses BBB)
Elimination:
HalfLife:
Acetaminophen: 1-4 hours; Diphenhydramine: 2.4-9.3 hours
Clearance:
Not available (variable)
ExcretionRoute:
Renal (primarily as metabolites)
Unchanged:
Acetaminophen: <5%; Diphenhydramine: <1%
Pharmacodynamics
OnsetOfAction:
Acetaminophen: 30-60 minutes (analgesia); Diphenhydramine: 15-60 minutes (sedation)
PeakEffect:
Acetaminophen: 1-2 hours (analgesia); Diphenhydramine: 1-3 hours (sedation)
DurationOfAction:
Acetaminophen: 4-6 hours (analgesia); Diphenhydramine: 4-8 hours (sedation)
Safety & Warnings
BLACK BOX WARNING
Acetaminophen has been associated with cases of acute liver failure, at times resulting in liver transplant or death. Most of the cases of liver injury are associated with the use of acetaminophen at doses that exceed 4000 mg per day, and often involve more than one acetaminophen-containing product. Serious skin reactions, such as Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP), have been reported rarely in patients taking acetaminophen. Discontinue Panadol PM immediately and contact your healthcare provider if you develop skin rash or blistering.
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. If you notice any of the following symptoms, contact your doctor or seek immediate 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
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of liver problems, including:
+ Dark urine
+ Fatigue
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellow skin or eyes
Urination problems, such as:
+ Inability to pass urine
+ Changes in urine output
Severe skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis), characterized by:
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Red or irritated eyes
+ Sores in the mouth, throat, nose, or eyes
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 persist, contact your doctor:
Drowsiness
Feeling nervous and excitable
Reporting Side Effects
This list is not exhaustive, and you may experience other 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 immediate 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
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of liver problems, including:
+ Dark urine
+ Fatigue
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellow skin or eyes
Urination problems, such as:
+ Inability to pass urine
+ Changes in urine output
Severe skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis), characterized by:
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Red or irritated eyes
+ Sores in the mouth, throat, nose, or eyes
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 persist, contact your doctor:
Drowsiness
Feeling nervous and excitable
Reporting Side Effects
This list is not exhaustive, and you may experience other 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:
- Signs of liver damage: yellowing of skin or eyes (jaundice), dark urine, clay-colored stools, severe stomach pain, nausea, vomiting, unusual tiredness.
- Signs of allergic reaction: rash, itching/swelling (especially of face/tongue/throat), severe dizziness, trouble breathing.
- Severe drowsiness or dizziness.
- Difficulty urinating.
- Blurred vision.
- Worsening of pain or insomnia after 10 days (pain) or 2 weeks (insomnia) of use.
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 liver disease, as this may affect your ability to take this medication.
Special Considerations for Children:
If the patient is under 12 years of age, do not administer this medication. It is not approved for use in children younger than 12 years.
Additional Precautions:
This medication may interact with other drugs or health conditions. Therefore, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
+ All prescription and over-the-counter (OTC) medications you are taking
+ Any natural products or vitamins you are using
+ Your health problems, including any medical conditions or diseases
* Before starting, stopping, or changing the dose of any medication, including this one, consult with your doctor to ensure your safety.
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 liver disease, as this may affect your ability to take this medication.
Special Considerations for Children:
If the patient is under 12 years of age, do not administer this medication. It is not approved for use in children younger than 12 years.
Additional Precautions:
This medication may interact with other drugs or health conditions. Therefore, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
+ All prescription and over-the-counter (OTC) medications you are taking
+ Any natural products or vitamins you are using
+ Your health problems, including any medical conditions or diseases
* Before starting, stopping, or changing the dose of any medication, including this one, consult with your doctor to ensure your safety.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Adhere strictly to the dosage instructions provided by your doctor, as taking more than prescribed may increase your risk of experiencing severe side effects. Do not exceed the recommended treatment duration, and only take this medication for the length of time specified by your doctor.
To ensure your safety, avoid operating a vehicle or engaging in any activities that require alertness while taking this medication. Additionally, refrain from consuming alcohol during treatment. Before using marijuana, other cannabis products, or any prescription or over-the-counter medications that may cause drowsiness, consult with your doctor.
This medication contains acetaminophen, which can cause liver problems in some individuals. In severe cases, liver damage has led to the need for a liver transplant or has been fatal. Liver problems are more likely to occur when taking more than 4,000 milligrams of acetaminophen per day, especially when combined with other medications containing acetaminophen. To minimize this risk, avoid taking other products that contain acetaminophen, and carefully check the labels of all medications. Follow the dosage instructions precisely, and do not exceed the recommended daily intake of acetaminophen. If you are unsure about the safe daily limit, consult your doctor or pharmacist. Some individuals, such as those with liver problems or children, may require a lower daily dose.
If you suspect you have taken too much acetaminophen, contact your doctor immediately, even if you do not experience any symptoms. Do not use this medication in conjunction with other products containing diphenhydramine.
As this medication may interfere with certain laboratory tests, inform all your healthcare providers and laboratory personnel that you are taking this medication. If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects. Similarly, if the patient is a child, use this medication with caution, as children may be at a higher risk of experiencing excitability.
If you are pregnant, planning to become pregnant, or breastfeeding, consult your doctor to discuss the potential benefits and risks to you and your baby.
To ensure your safety, avoid operating a vehicle or engaging in any activities that require alertness while taking this medication. Additionally, refrain from consuming alcohol during treatment. Before using marijuana, other cannabis products, or any prescription or over-the-counter medications that may cause drowsiness, consult with your doctor.
This medication contains acetaminophen, which can cause liver problems in some individuals. In severe cases, liver damage has led to the need for a liver transplant or has been fatal. Liver problems are more likely to occur when taking more than 4,000 milligrams of acetaminophen per day, especially when combined with other medications containing acetaminophen. To minimize this risk, avoid taking other products that contain acetaminophen, and carefully check the labels of all medications. Follow the dosage instructions precisely, and do not exceed the recommended daily intake of acetaminophen. If you are unsure about the safe daily limit, consult your doctor or pharmacist. Some individuals, such as those with liver problems or children, may require a lower daily dose.
If you suspect you have taken too much acetaminophen, contact your doctor immediately, even if you do not experience any symptoms. Do not use this medication in conjunction with other products containing diphenhydramine.
As this medication may interfere with certain laboratory tests, inform all your healthcare providers and laboratory personnel that you are taking this medication. If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects. Similarly, if the patient is a child, use this medication with caution, as children may be at a higher risk of experiencing excitability.
If you are pregnant, planning to become pregnant, or breastfeeding, consult your doctor to discuss the potential benefits and risks to you and your baby.
Overdose Information
Overdose Symptoms:
- Acetaminophen overdose: Nausea, vomiting, abdominal pain, loss of appetite, sweating, extreme tiredness, yellowing of skin or eyes (jaundice). These symptoms may not appear until 24-48 hours after ingestion.
- Diphenhydramine overdose: Severe drowsiness, confusion, hallucinations, seizures, dilated pupils, dry mouth, flushed skin, rapid heartbeat, urinary retention, coma.
What to Do:
In case of overdose, seek immediate medical attention. Call 911 or Poison Control at 1-800-222-1222. Activated charcoal may be administered if within a few hours of ingestion. For acetaminophen overdose, N-acetylcysteine (NAC) is the antidote and should be administered as soon as possible. Supportive care for diphenhydramine overdose.
Drug Interactions
Contraindicated Interactions
- Monoamine Oxidase Inhibitors (MAOIs) or within 14 days of stopping MAOIs (due to diphenhydramine, can prolong and intensify anticholinergic and CNS depressant effects)
Major Interactions
- Alcohol (increased risk of hepatotoxicity with acetaminophen, increased CNS depression with diphenhydramine)
- Other CNS depressants (e.g., opioids, benzodiazepines, sedatives, hypnotics, tricyclic antidepressants, antipsychotics - increased sedation and respiratory depression with diphenhydramine)
- Anticholinergic drugs (e.g., atropine, scopolamine, some antipsychotics, tricyclic antidepressants - increased risk of anticholinergic side effects like dry mouth, urinary retention, constipation, confusion with diphenhydramine)
- Warfarin (Acetaminophen may increase INR, especially with chronic high doses)
Moderate Interactions
- Other hepatotoxic drugs (increased risk of liver injury with acetaminophen)
- Cholestyramine (reduces acetaminophen absorption if given concurrently)
- Metoclopramide (increases acetaminophen absorption rate)
- Phenytoin, Carbamazepine, Barbiturates, Rifampin (may increase acetaminophen hepatotoxicity by inducing CYP2E1)
- Other antihistamines (additive sedative and anticholinergic effects)
Minor Interactions
- None commonly cited for significant clinical impact with typical OTC use.
Monitoring
Baseline Monitoring
Liver function tests (ALT, AST, Bilirubin)
Rationale: To establish baseline in patients with pre-existing liver conditions or risk factors for hepatotoxicity (e.g., chronic alcohol use).
Timing: Prior to initiation if risk factors present, otherwise not routinely needed for short-term OTC use.
Renal function (BUN, Creatinine)
Rationale: To assess baseline kidney function, especially in elderly or those with known renal impairment, as diphenhydramine is renally eliminated.
Timing: Prior to initiation if risk factors present, otherwise not routinely needed for short-term OTC use.
Routine Monitoring
Symptoms of pain relief and sedation
Frequency: Daily, during use
Target: Adequate symptom control without excessive sedation
Action Threshold: If pain persists or worsens, or if excessive drowsiness occurs, discontinue and consult a healthcare provider.
Signs of liver injury (e.g., jaundice, dark urine, abdominal pain)
Frequency: Daily, during use
Target: Absence of signs
Action Threshold: Immediately discontinue and seek medical attention if any signs of liver injury appear.
Signs of anticholinergic effects (e.g., dry mouth, blurred vision, urinary retention, constipation, confusion)
Frequency: Daily, during use
Target: Absence of or tolerable mild effects
Action Threshold: If severe or intolerable, discontinue and consult a healthcare provider.
Symptom Monitoring
- Effectiveness of pain relief
- Degree of sedation/drowsiness
- Dry mouth
- Blurred vision
- Urinary retention
- Constipation
- Dizziness
- Confusion (especially in elderly)
- Nausea, vomiting, abdominal pain (signs of liver injury)
- Yellowing of skin or eyes (jaundice)
- Dark urine
Special Patient Groups
Pregnancy
Generally considered Category B. Acetaminophen is widely used in pregnancy and considered low risk. Diphenhydramine is also Category B, but its use, especially in the third trimester, should be discussed with a healthcare provider due to potential for neonatal effects (e.g., irritability, tremors). Use only if clearly needed and benefits outweigh risks.
Trimester-Specific Risks:
First Trimester:
Low risk for both components.
Second Trimester:
Low risk for both components.
Third Trimester:
Diphenhydramine use near term may theoretically cause irritability or tremors in the neonate due to anticholinergic effects. Acetaminophen remains low risk.
Lactation
Lactation Risk L3 (Moderately Safe). Both acetaminophen and diphenhydramine are excreted into breast milk. Acetaminophen is generally considered safe for breastfeeding. Diphenhydramine can cause drowsiness in the infant and may decrease milk supply, especially with regular use. Use with caution, observe infant for sedation, and consider alternatives if possible.
Infant Risk:
Acetaminophen: Low risk. Diphenhydramine: Moderate risk of infant sedation, irritability, or decreased milk supply.
Pediatric Use
Not recommended for children under 12 years of age for sleep aid due to the diphenhydramine component, which can cause paradoxical excitation in some children. Acetaminophen has specific pediatric dosing for pain/fever, but this combination product is not formulated for general pediatric use.
Geriatric Use
Use with caution in elderly patients (65 years and older) due to increased sensitivity to the anticholinergic effects of diphenhydramine (e.g., confusion, dizziness, urinary retention, constipation, falls). Start with the lowest effective dose and monitor closely for adverse effects. Avoid if possible in patients with dementia or prostatic hypertrophy.
Clinical Information
Clinical Pearls
- This product is intended for short-term use (up to 10 days for pain, 2 weeks for insomnia). Prolonged use should be under medical supervision.
- Advise patients about the risk of liver damage with acetaminophen, especially if exceeding the maximum daily dose or combining with other acetaminophen-containing products.
- Warn patients about significant drowsiness and anticholinergic side effects (dry mouth, blurred vision, urinary retention, constipation) due to diphenhydramine.
- Emphasize avoiding alcohol and other CNS depressants while taking this medication.
- Not suitable for chronic insomnia or chronic pain; address underlying causes with a healthcare provider.
Alternative Therapies
- For pain: NSAIDs (ibuprofen, naproxen), other single-ingredient acetaminophen products.
- For sleep: Melatonin, valerian root, doxylamine, non-benzodiazepine hypnotics (prescription), cognitive behavioral therapy for insomnia (CBT-I).
- For pain and sleep: Separate single-ingredient products (e.g., acetaminophen for pain, melatonin for sleep) to allow for more flexible dosing and avoid unnecessary exposure to one component.
Cost & Coverage
Average Cost:
$5 - $20 per 20-50 tablets
Generic Available:
Yes
Insurance Coverage:
Generally not covered by prescription drug plans as it is an over-the-counter (OTC) medication. May be eligible for FSA/HSA reimbursement.
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 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 emergency medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.