Tencon 50mg/325mg Tablets
WARNING: This drug has acetaminophen in it. Liver problems have happened with the use of acetaminophen. Sometimes, this has led to a liver transplant or death. Most of the time, liver problems happened in people taking more than 4,000 mg (milligrams) of acetaminophen in a day. People were also often taking more than 1 drug that had acetaminophen. @ COMMON USES: It is used to treat tension headaches.
Drug Class
Analgesic, Barbiturate
Pharmacologic Class
Barbiturate (Butalbital), Para-aminophenol derivative (Acetaminophen)
Pregnancy Category
Category C
FDA Approved
Mar 1984
DEA Schedule
Schedule III
Overview
What is this medicine?
Tencon is a combination medicine containing butalbital, a sedative, and acetaminophen, a pain reliever. It is used to treat tension headaches. Butalbital helps you relax, and acetaminophen helps reduce pain.
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
Keep your medication at room temperature, away from light and moisture. Avoid storing it in a bathroom. To prevent accidental ingestion, store it in a secure location where children and pets cannot access it. Consider using a locked box or area to keep it safe from others. 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 or explore local drug take-back programs.
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 once or extra doses. If you take this medication as needed, follow your doctor's instructions and do not take it more frequently than recommended.
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
Keep your medication at room temperature, away from light and moisture. Avoid storing it in a bathroom. To prevent accidental ingestion, store it in a secure location where children and pets cannot access it. Consider using a locked box or area to keep it safe from others. 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 or explore local drug take-back programs.
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 once or extra doses. If you take this medication as needed, follow your doctor's instructions and do not take it more frequently than recommended.
Lifestyle & Tips
- Do not take more than the prescribed dose, as this can lead to serious liver damage or overdose.
- Avoid alcohol while taking this medication, as it can increase the risk of liver damage and severe drowsiness.
- Do not take other medicines that contain acetaminophen (Tylenol, many cold/flu remedies) to avoid accidental overdose.
- This medicine can cause drowsiness or dizziness. Do not drive or operate heavy machinery until you know how it affects you.
- This medication can be habit-forming. Use exactly as prescribed and do not use for longer than recommended.
- If you use this medication regularly for headaches, you may develop 'medication overuse headaches' (rebound headaches). Talk to your doctor if your headaches worsen or become more frequent.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
1 to 2 tablets every 4 hours as needed
Dose Range:
1 - 2 mg
Condition-Specific Dosing:
maximumDailyDose:
Not to exceed 6 tablets per day (300mg Butalbital, 1950mg Acetaminophen)
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established (safety and efficacy not established; generally not recommended)
Dose Adjustments
Renal Impairment:
Mild:
Use with caution; monitor for accumulation
Moderate:
Use with caution; consider dose reduction and extended dosing interval
Severe:
Contraindicated or not recommended due to risk of accumulation and toxicity
Dialysis:
Not well studied; Acetaminophen is dialyzable, Butalbital is less so. Avoid use.
Hepatic Impairment:
Mild:
Use with caution; monitor liver function
Moderate:
Consider dose reduction and extended dosing interval; monitor liver function closely
Severe:
Contraindicated due to risk of hepatotoxicity from Acetaminophen and impaired Butalbital metabolism
Confidence:
Medium
Pharmacology
Mechanism of Action
Butalbital: A barbiturate that produces generalized central nervous system depression, likely through its binding to the GABA-A receptor complex, enhancing the inhibitory effects of GABA. Acetaminophen: A non-opioid, non-salicylate analgesic and antipyretic. Its mechanism of action is thought to involve inhibition of prostaglandin synthesis primarily in the central nervous system, with minimal peripheral anti-inflammatory effects.
Pharmacokinetics
Absorption:
Bioavailability:
Butalbital: ~90%; Acetaminophen: 60-90%
Tmax:
Butalbital: ~2 hours; Acetaminophen: 0.5-2 hours
FoodEffect:
Food may delay Acetaminophen absorption but not significantly affect extent of absorption. No significant effect on Butalbital.
Distribution:
Vd:
Butalbital: ~1 L/kg; Acetaminophen: ~0.95 L/kg
ProteinBinding:
Butalbital: ~45%; Acetaminophen: 10-25%
CnssPenetration:
Yes
Elimination:
HalfLife:
Butalbital: ~35-40 hours; Acetaminophen: 1-4 hours
Clearance:
Not available
ExcretionRoute:
Renal (primarily as metabolites)
Unchanged:
Butalbital: <5%; Acetaminophen: <5%
Pharmacodynamics
OnsetOfAction:
30-60 minutes
PeakEffect:
1-2 hours
DurationOfAction:
4-6 hours (limited by acetaminophen component)
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 milligrams per day, and often involve more than one acetaminophen-containing product. Serious skin reactions (Stevens-Johnson Syndrome, Toxic Epidermal Necrolysis, Acute Generalized Exanthematous Pustulosis) have been reported with the use of acetaminophen. Discontinue Tencon at the first appearance of skin rash or any other sign of hypersensitivity.
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
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of liver problems, including:
+ Dark urine
+ Tiredness
+ 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
Shortness of breath
Neurological symptoms, including:
+ Slurred speech
+ Stumbling
+ Confusion
+ Excessive sleepiness or dizziness
+ Feeling drunk
Severe skin reactions, such as Stevens-Johnson syndrome or toxic epidermal necrolysis, which can cause:
+ 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
Most people experience either no side effects or only mild side effects while taking this medication. However, if you notice any of the following side effects or any other unusual symptoms, contact your doctor or seek medical attention:
Dizziness or sleepiness
Stomach pain
* Upset stomach or vomiting
Reporting Side Effects
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.
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
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of liver problems, including:
+ Dark urine
+ Tiredness
+ 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
Shortness of breath
Neurological symptoms, including:
+ Slurred speech
+ Stumbling
+ Confusion
+ Excessive sleepiness or dizziness
+ Feeling drunk
Severe skin reactions, such as Stevens-Johnson syndrome or toxic epidermal necrolysis, which can cause:
+ 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
Most people experience either no side effects or only mild side effects while taking this medication. However, if you notice any of the following side effects or any other unusual symptoms, contact your doctor or seek medical attention:
Dizziness or sleepiness
Stomach pain
* Upset stomach or vomiting
Reporting Side Effects
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:
- Signs of liver damage: nausea, vomiting, loss of appetite, dark urine, clay-colored stools, yellowing of your skin or eyes (jaundice), upper stomach pain.
- Signs of a severe skin reaction: fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling.
- Signs of an allergic reaction: hives, difficulty breathing, swelling of your face, lips, tongue, or throat.
- Extreme drowsiness or difficulty waking up.
- Slow or shallow 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.
Certain health conditions, including liver disease or porphyria, as these may affect your ability to take this medication safely.
This list is not exhaustive, and it is crucial to discuss all your medications, health problems, and concerns with your doctor and pharmacist. This includes:
All prescription and over-the-counter (OTC) medications you are currently taking
Any natural products or vitamins you are using
* 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, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, including liver disease or porphyria, as these may affect your ability to take this medication safely.
This list is not exhaustive, and it is crucial to discuss all your medications, health problems, and concerns with your doctor and pharmacist. This includes:
All prescription and over-the-counter (OTC) medications you are currently taking
Any natural products or vitamins you are using
* 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
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
While taking this medication, avoid driving and engaging in other activities that require alertness, as it may impair your ability to perform these tasks safely.
Risk of Dependence and Tolerance
Long-term use of this medication may lead to dependence. Do not take this medication for an extended period beyond what your doctor has prescribed. If you have been taking this medication for a long time or at high doses, you may develop tolerance, which means you may need higher doses to achieve the same effect. If you notice that the medication is not working as well as it used to, contact your doctor. Do not take more than the prescribed dose.
Withdrawal Symptoms
If you have been taking this medication regularly and suddenly stop, you may experience withdrawal symptoms. Do not stop taking this medication abruptly without consulting your doctor. If you experience any adverse effects, inform your doctor promptly.
Acetaminophen Precautions
Be cautious when taking other products that contain acetaminophen, as excessive acetaminophen consumption can cause liver problems. Carefully check the labels of other medications and supplements to avoid accidental overdose. If you are unsure about the safe amount of acetaminophen you can take in a day, consult your doctor or pharmacist. The maximum daily dose of acetaminophen is 4,000 mg (milligrams) for some individuals, but people with liver problems or children may require lower doses. If you suspect you have taken too much acetaminophen in a day, contact your doctor immediately, even if you feel well.
Interference with Lab Tests
This medication may affect certain laboratory tests. Inform all your healthcare providers and lab personnel that you are taking this medication.
Substance Interactions
Avoid consuming alcohol, marijuana, or other forms of cannabis, as well as prescription or over-the-counter (OTC) medications that may slow your reactions, as they may interact with this medication.
Special Precautions
If you have a deficiency of the enzyme G6PD, you may be at risk of developing anemia. This deficiency is more common in individuals of African, South Asian, Middle Eastern, and Mediterranean descent. Exercise caution when taking this medication.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.
* If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks of this medication with your doctor to ensure safe use.
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
While taking this medication, avoid driving and engaging in other activities that require alertness, as it may impair your ability to perform these tasks safely.
Risk of Dependence and Tolerance
Long-term use of this medication may lead to dependence. Do not take this medication for an extended period beyond what your doctor has prescribed. If you have been taking this medication for a long time or at high doses, you may develop tolerance, which means you may need higher doses to achieve the same effect. If you notice that the medication is not working as well as it used to, contact your doctor. Do not take more than the prescribed dose.
Withdrawal Symptoms
If you have been taking this medication regularly and suddenly stop, you may experience withdrawal symptoms. Do not stop taking this medication abruptly without consulting your doctor. If you experience any adverse effects, inform your doctor promptly.
Acetaminophen Precautions
Be cautious when taking other products that contain acetaminophen, as excessive acetaminophen consumption can cause liver problems. Carefully check the labels of other medications and supplements to avoid accidental overdose. If you are unsure about the safe amount of acetaminophen you can take in a day, consult your doctor or pharmacist. The maximum daily dose of acetaminophen is 4,000 mg (milligrams) for some individuals, but people with liver problems or children may require lower doses. If you suspect you have taken too much acetaminophen in a day, contact your doctor immediately, even if you feel well.
Interference with Lab Tests
This medication may affect certain laboratory tests. Inform all your healthcare providers and lab personnel that you are taking this medication.
Substance Interactions
Avoid consuming alcohol, marijuana, or other forms of cannabis, as well as prescription or over-the-counter (OTC) medications that may slow your reactions, as they may interact with this medication.
Special Precautions
If you have a deficiency of the enzyme G6PD, you may be at risk of developing anemia. This deficiency is more common in individuals of African, South Asian, Middle Eastern, and Mediterranean descent. Exercise caution when taking this medication.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.
* If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks of this medication with your doctor to ensure safe use.
Overdose Information
Overdose Symptoms:
- Acetaminophen overdose: nausea, vomiting, stomach pain, loss of appetite, dark urine, yellowing of skin or eyes (jaundice), confusion, sweating, extreme tiredness.
- Butalbital overdose: severe drowsiness, confusion, slow or shallow breathing, weak pulse, cold or clammy skin, fainting, coma.
What to Do:
Seek immediate medical attention. Call 911 or Poison Control at 1-800-222-1222. Overdose requires urgent treatment, especially for acetaminophen toxicity (e.g., N-acetylcysteine).
Drug Interactions
Contraindicated Interactions
- Other Acetaminophen-containing products (risk of overdose)
- Severe hepatic impairment
Major Interactions
- Alcohol (increased risk of hepatotoxicity and CNS depression)
- Other CNS depressants (e.g., opioids, benzodiazepines, sedatives, hypnotics, tricyclic antidepressants, antihistamines) - additive CNS depression
- Warfarin (Acetaminophen can increase INR with chronic high doses)
- Hepatotoxic drugs (increased risk of liver injury with Acetaminophen)
- CYP3A4 inducers (e.g., Rifampin, Carbamazepine, Phenytoin) - may decrease Butalbital levels, but Butalbital itself is an inducer, leading to complex interactions.
Moderate Interactions
- Cholestyramine (reduces Acetaminophen absorption)
- Lamotrigine (Butalbital may decrease lamotrigine levels)
- Oral contraceptives (Butalbital may decrease efficacy)
- Zidovudine (Acetaminophen may increase zidovudine levels)
Minor Interactions
- Metoclopramide (may increase Acetaminophen absorption rate)
Monitoring
Baseline Monitoring
Liver Function Tests (ALT, AST, Bilirubin)
Rationale: To assess baseline hepatic function due to Acetaminophen's hepatotoxicity risk.
Timing: Prior to initiation, especially in patients with risk factors for liver disease.
Renal Function (BUN, Creatinine)
Rationale: To assess baseline renal function as metabolites are renally excreted.
Timing: Prior to initiation, especially in patients with renal impairment.
Routine Monitoring
Pain/Headache Severity and Frequency
Frequency: Regularly during therapy, especially if used for chronic conditions.
Target: Reduction in pain/headache intensity and frequency.
Action Threshold: Lack of efficacy or worsening symptoms may indicate need for re-evaluation or alternative therapy; increased frequency of use may indicate medication overuse headache or dependence.
Signs and Symptoms of CNS Depression
Frequency: Daily, especially during initiation or dose changes.
Target: Absence of excessive drowsiness, dizziness, impaired coordination.
Action Threshold: Significant sedation, confusion, or respiratory depression requires immediate medical attention and dose adjustment/discontinuation.
Signs and Symptoms of Hepatotoxicity
Frequency: Periodically, or if symptoms develop (e.g., nausea, vomiting, abdominal pain, dark urine, jaundice).
Target: Absence of symptoms.
Action Threshold: Any signs of liver injury warrant immediate discontinuation and medical evaluation, including LFTs.
Symptom Monitoring
- Excessive drowsiness
- Dizziness
- Lightheadedness
- Nausea
- Vomiting
- Abdominal pain (especially upper right quadrant)
- Dark urine
- Jaundice (yellowing of skin or eyes)
- Unusual bleeding or bruising
- Skin rash or blistering
- Difficulty breathing
- Confusion
- Mood changes
Special Patient Groups
Pregnancy
Category C. Should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Butalbital can cause fetal harm and neonatal withdrawal symptoms.
Trimester-Specific Risks:
First Trimester:
Potential for congenital malformations with barbiturates.
Second Trimester:
Risk of fetal CNS depression and respiratory depression.
Third Trimester:
Risk of neonatal withdrawal symptoms (e.g., tremors, hypertonia, irritability, feeding difficulties) if used chronically, and respiratory depression at delivery.
Lactation
L3 (Moderately Safe). Both Butalbital and Acetaminophen are excreted in breast milk. Butalbital can cause sedation in the infant. Use with caution; monitor infant for drowsiness, poor feeding, and developmental milestones.
Infant Risk:
Risk of sedation, lethargy, and poor feeding in breastfed infants due to Butalbital. Acetaminophen is generally considered safe in usual doses.
Pediatric Use
Safety and efficacy have not been established in pediatric patients. Not recommended for use in children due to the risk of respiratory depression and other adverse effects associated with barbiturates.
Geriatric Use
Elderly patients may be more sensitive to the sedative and CNS depressant effects of butalbital. Lower doses and careful monitoring are recommended to avoid excessive sedation, dizziness, and increased risk of falls. Acetaminophen metabolism may also be altered in the elderly.
Clinical Information
Clinical Pearls
- High potential for medication overuse headache (MOH) if used frequently (e.g., >3 days/week). Patients should be educated on this risk and encouraged to limit use.
- Risk of physical dependence and withdrawal symptoms (e.g., seizures, delirium) upon abrupt discontinuation, especially after prolonged or high-dose use. Tapering is often necessary.
- Due to the long half-life of butalbital, cumulative effects and prolonged sedation can occur with repeated dosing.
- Always confirm if patients are taking other acetaminophen-containing products to prevent accidental overdose.
- Not recommended for chronic pain management due to dependence potential and risk of MOH.
Alternative Therapies
- NSAIDs (e.g., ibuprofen, naproxen) for tension headaches
- Triptans (e.g., sumatriptan, zolmitriptan) for migraine headaches
- Other analgesics (e.g., tramadol, non-barbiturate sedatives)
- Non-pharmacological treatments for headaches (e.g., stress management, biofeedback, physical therapy)
Cost & Coverage
Average Cost:
Varies widely, typically $10-$50 per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Tier 1 or 2 (generic)
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 emergency medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.