Phenobarb 130mg/ml Inj, 1ml

Phenobarbital is a barbiturate that produces nonselective depression of the central nervous system (CNS). It binds to the GABA-A receptor complex, enhancing the inhibitory effects of GABA by prolonging the opening of chloride channels, leading to neuronal hyperpolarization and decreased neuronal excitability. At high concentrations, it may also directly activate chloride channels.

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
Confusion
Balance problems
Muscle spasms
Bad dreams
Restlessness
Hallucinations (seeing or hearing things that are not there)
Shortness of breath
Slow heartbeat
Feeling extremely tired or weak
Severe dizziness or fainting

Severe Skin Reaction (Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis)

This rare but serious condition can cause severe health problems and may be life-threatening. Seek medical help immediately if you experience:

Red, swollen, blistered, or peeling skin (with or without fever)
Red or irritated eyes
Sores in your mouth, throat, nose, or eyes

Blood Disorder and Organ Damage

A severe and potentially life-threatening effect has occurred in people taking seizure medications like this one. Contact your doctor right away if you experience:

Swollen glands
Fever
Rash
Painful sores in the mouth or around the eyes
Chest pain
Signs of kidney problems, such as:
+ Unable to pass urine
+ Change in the amount of urine passed
Signs of liver problems, such as:
+ Dark urine
+ Tiredness
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellow skin or eyes

Administration-Related Side Effects

If this medication is administered too quickly, it can cause:

Breathing difficulties
Signs of high or low blood pressure, such as:
+ Severe headache
+ Dizziness
+ Fainting
+ Changes in vision

Tell your doctor immediately if you experience any of these symptoms.

Tissue Damage

If the medication leaks from the vein, it can cause tissue damage. Inform your nurse if you notice:

Redness
Burning
Pain
Swelling
Blisters
Skin sores
Fluid leakage at the injection site

Other Side Effects

Most people do not experience significant side effects, but some may occur. Contact your doctor or seek medical help if you experience any of the following:

Dizziness or drowsiness
Headache
Upset stomach or vomiting
Constipation
Feeling nervous or excitable
Sleep disturbances
* Irritation at the injection site

These are not all the possible side effects that may occur. If you have 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.

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. Describe the allergic reaction and its symptoms.
Existing health conditions, such as liver disease or breathing difficulties (e.g., shortness of breath).
A history of porphyria, a rare genetic disorder.
Certain heart conditions, including:
+ Heart failure
+ Unstable angina (a type of chest pain)
+ Abnormal heartbeat (e.g., long QT interval on an electrocardiogram (ECG))
+ Kidney disease
+ Low thyroid function (hypothyroidism)
+ Aortic stenosis (a very narrow heart valve)
Recent heart attack
Use of medications that can cause abnormal heart rhythms (prolonged QT interval). There are many medications that can have this effect; consult your doctor or pharmacist if you are unsure.

Special Considerations for Newborns and Infants:

Some formulations of this medication may contain benzyl alcohol, which can cause severe and potentially life-threatening side effects in newborns and infants. Your doctor will weigh the benefits and risks of using this medication in these age groups.

Interactions with Other Medications and Health Conditions:

This is not an exhaustive list of all potential interactions. It is crucial to inform your doctor and pharmacist about all your medications, including:
+ Prescription and over-the-counter (OTC) medications
+ Natural products
+ Vitamins
Share information about your health problems to ensure safe use of this medication.
Do not start, stop, or change the dose of any medication without consulting your doctor.

Important Warnings and Cautions

When taking this medication, it is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, about your treatment.

Risk of Dependence and Withdrawal
The longer you take this medication and the higher the dose, the greater your risk of dependence and withdrawal. Before reducing the dose or stopping the medication, consult your doctor and follow their instructions carefully. Abruptly lowering the dose or stopping the medication can lead to withdrawal, which may be life-threatening. Seek immediate medical attention if you experience any adverse effects.

Tolerance
If you have been taking this medication for an extended period or at high doses, you may develop tolerance, requiring higher doses to achieve the same effect. If you notice the medication is not working as well as it previously did, contact your doctor. Do not take more than the prescribed dose.

Monitoring and Precautions
If you are taking this medication long-term, your doctor may recommend regular blood tests. Discuss this with your doctor. Until you understand how this medication affects you, avoid driving and other activities that require alertness. Additionally, refrain from consuming alcohol while taking this medication.

Interactions with Other Substances
Before using marijuana, other forms of cannabis, or prescription or over-the-counter drugs that may cause drowsiness, consult your doctor.

Suicidal Thoughts and Actions
Like other seizure medications, this drug may rarely increase the risk of suicidal thoughts or actions, particularly in individuals with a history of such behaviors. Immediately contact your doctor if you experience new or worsening symptoms, such as depression, nervousness, restlessness, irritability, panic attacks, or mood changes. If you have suicidal thoughts or actions, seek medical attention right away.

Special Considerations
If you are 65 or older, use this medication with caution, as you may be more susceptible to side effects. When used in children, this medication requires careful consideration, as the risk of certain side effects may be higher.

Birth Control and Pregnancy
Birth control pills and other hormone-based birth control methods may be less effective while taking this medication. Use two forms of birth control to prevent pregnancy. If you become pregnant or are planning to become pregnant, inform your doctor, as this medication may harm the unborn baby. If you take this medication during the third trimester of pregnancy, your newborn may experience side effects or withdrawal.

Breastfeeding
If you are breastfeeding, consult your doctor to discuss potential risks to your baby.

Seizure Management
If your seizures change or worsen after starting this medication, consult your doctor to adjust your treatment plan as needed.

• Porphyria (acute intermittent porphyria)

• Other CNS depressants (e.g., opioids, benzodiazepines, alcohol, tricyclic antidepressants, antihistamines) - increased sedation and respiratory depression
• Valproic acid - increases phenobarbital levels (inhibits metabolism), leading to toxicity
• Chloramphenicol - increases phenobarbital levels
• Oral contraceptives - decreased efficacy of contraceptives (phenobarbital is a strong enzyme inducer)
• Warfarin - decreased anticoagulant effect (phenobarbital induces metabolism of warfarin)
• Corticosteroids - decreased corticosteroid effect
• Doxycycline - decreased doxycycline levels
• Griseofulvin - decreased griseofulvin levels
• Lamotrigine - decreased lamotrigine levels
• Tiagabine - decreased tiagabine levels
• Felbamate - increased phenobarbital levels

• Carbamazepine - decreased phenobarbital levels (enzyme induction), decreased carbamazepine levels
• Phenytoin - variable effect on phenobarbital levels (can increase or decrease), decreased phenytoin levels
• Rifampin - decreased phenobarbital levels
• Theophylline/Aminophylline - decreased theophylline/aminophylline levels
• Verapamil - increased phenobarbital levels
• Disulfiram - increased phenobarbital levels

• Folic acid - may decrease phenobarbital levels or increase seizure frequency in some patients

• Excessive sedation
• Drowsiness
• Dizziness
• Ataxia (unsteadiness)
• Nystagmus (involuntary eye movements)
• Respiratory depression (slow, shallow breathing)
• Confusion
• Irritability
• Skin rash (Stevens-Johnson syndrome, toxic epidermal necrolysis)
• Fever
• Sore throat
• Unusual bleeding or bruising
• Yellowing of skin or eyes (jaundice)

Phenobarbital is classified as Pregnancy Category D, indicating positive evidence of human fetal risk. It is associated with an increased risk of major congenital malformations (e.g., cardiac defects, cleft lip/palate, neural tube defects) and a fetal barbiturate withdrawal syndrome if used during the third trimester. Use only if the potential benefit outweighs the risk.

Phenobarbital is excreted into breast milk and can cause significant sedation, poor feeding, and withdrawal symptoms in breastfed infants. The American Academy of Pediatrics considers it a drug for which the effect on nursing infants is unknown but may be of concern. Use with caution; monitor infant for sedation, poor weight gain, and developmental milestones. Consider alternative agents or bottle feeding if infant effects are significant.

Neonates and infants have a prolonged half-life due to immature hepatic metabolism, requiring careful dosing and monitoring. Children generally metabolize phenobarbital faster than adults, often requiring higher mg/kg doses. Close monitoring of serum levels and clinical response is crucial due to age-dependent pharmacokinetic variability.

Elderly patients may be more sensitive to the CNS depressant effects of phenobarbital (e.g., sedation, ataxia, confusion) and are at increased risk of falls. Lower initial doses and slower titration are recommended. Monitor renal and hepatic function closely, as age-related decline in these functions can prolong phenobarbital's half-life.

• Phenobarbital has a very long half-life, meaning it takes a long time to reach steady state (weeks) and to be eliminated from the body. This makes dose adjustments slow and requires patience.
• Therapeutic drug monitoring (TDM) is essential for phenobarbital to ensure efficacy and minimize toxicity, especially given its narrow therapeutic index.
• IV administration should be slow (50-100 mg/min in adults, 1-3 mg/kg/min in children) to avoid respiratory depression and hypotension.
• Due to its enzyme-inducing properties, phenobarbital can significantly reduce the effectiveness of many other medications, including oral contraceptives, warfarin, and other anticonvulsants. Always review concomitant medications.
• Abrupt discontinuation can precipitate severe withdrawal symptoms, including status epilepticus. Tapering is crucial.
• While effective, its significant sedative effects and drug interactions have led to its decreased use as a first-line agent for chronic seizure management, but it remains a critical drug for status epilepticus.

• For Status Epilepticus: Lorazepam, Diazepam, Midazolam, Fosphenytoin, Levetiracetam, Valproic acid.
• For Seizure Prophylaxis: Carbamazepine, Phenytoin, Valproic acid, Levetiracetam, Lamotrigine, Topiramate, Oxcarbazepine, Gabapentin, Pregabalin, Zonisamide, Lacosamide.
• For Sedation/Hypnosis: Benzodiazepines (e.g., Lorazepam, Diazepam, Midazolam), Propofol, Dexmedetomidine.

If your symptoms or health problems do not improve or worsen over time, it is essential to contact your doctor for further evaluation and guidance. To ensure safe use, never share your medication with others, and do not take medication prescribed to someone else. Store all medications in a secure location, out of reach of children and pets, to prevent accidental ingestion. Properly dispose of unused or expired medications by checking with your pharmacist for guidance on the best disposal method. Unless instructed to do so, avoid flushing medications down the toilet or pouring them down the drain, as this can harm the environment. Many communities have drug take-back programs; your pharmacist can provide information on these programs. Some medications may come with an additional patient information leaflet; consult your pharmacist if you have questions. If you have concerns or questions about your medication, 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. Be prepared to provide information about the medication taken, the amount, and the time it occurred to ensure prompt and effective treatment.