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Active substance(s): PHENOBARBITONE

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Phenobarbitone 15mg, 30mg and 60mg tablets
Read all of this leaflet carefully before you start taking this medicine because it contains
important information for you.
• Keep this leaflet. You may need to read it again.
• If you have any further questions, ask your doctor or pharmacist.
• This medicine has been prescribed for you only. Do not pass it on to others. It may harm them,
even if their signs of illness are the same as yours.
• If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible
side effects not listed in this leaflet. See section 4.
What is in this leaflet:
1. What Phenobarbitone tablets are and what they are used for
2. What you need to know before you take Phenobarbital Tablets
3. How to take Phenobarbital Tablets
4. Possible side effects
5. How to store Phenobarbital Tablets
6. Contents of the pack and other information
1. What Phenobarbitone tablets are and what they are used for
Phenobarbitone tablets belong to a group of medicines called barbiturates. These
medicines reduce brain activity which would otherwise cause fits or seizures in epilepsy, except
absence seizures (day dreaming).
2. What you need to know before you take Phenobarbital Tablets
Do not take Phenobarbitone tablets and tell your doctor if you have:
• an allergy (hypersensitivity) to Phenobarbitone, other barbiturates or any of the other
ingredients (see section 6)
• porphyria (a genetic or inherited disorder of the red blood pigment haemoglobin)
• severe breathing difficulties
• severe kidney or liver disease.
If you develop a rash or the following skin symptoms, seek immediate advice from a doctor
and tell that you are taking this medicine:
• Potentially life-threatening skin rashes (Stevens-Johnson syndrome, toxic epidermal necrolysis)
have been reported with the use of Phenobarbitone tablets appearing initially as reddish targetlike spots or circular patches often with central blisters on the trunk. Additional signs to look for
include ulcers in the mouth, throat, nose, genitals and conjunctivitis (red and swollen eyes). These
potentially life-threatening skin rashes are often accompanied by flu-like symptoms. The rash
may progress to widespread blistering or peeling of the skin. The highest risk for occurrence of
serious skin reactions is within the first weeks of treatment.
• If you have developed Stevens-Johnson syndrome or toxic epidermal necrolysis with the use of
Phenobarbitone tablets you must not be re-started on Phenobarbitone tablets at any time.

Warnings and precautions
Talk to your doctor or pharmacist before taking Phenobarbital tablets if you:
• or the person taking these tablets are young, run down, senile or have a history of drug abuse
or alcoholism
• have kidney or liver problems
• have breathing difficulties
• have sleeplessness due to severe or long term pain
A small number of people being treated with anti-epileptics such as Phenobarbitone have had
thoughts of harming or killing themselves. If at any time you have these thoughts, immediately
contact your doctor.
Other medicines and Phenobarbitone tablets
Tell your doctor or pharmacist if you are taking or have recently taken any other
medicines, or might take any other medicines. Especially:
• disopyramide and quinidine (to treat irregular heartbeats)
• chloramphenicol, doxycycline, metronidazole, rifampicin, telithromycin, griseofluvin,
itraconazole, posaconazole, voriconazole. abacavir, amprenavir, lopinavir, indinavir, darunavir,
nelfinavir and saquinavir (to treat infections)
• medicines used to thin the blood such as warfarin
• mianserin, paroxetine, MAOI or tricyclic antidepressants or St Johns’s wort
(Hypericumperforatum) a herbal remedy (to treat depression)
• oxcarbazepine, primidone, phenytoin, sodium valproate, carbamazepine, lamotrigine, tiagabine,
zonisamide, ethosuxamide and vigabatrin (to treat epilepsy)
• chlorpromazine, thioridazine, haloperidol, aripiprazole and clonazepam (to treat mental
•felodipine, verapamil, diltiazem, nimodipine, nifedipine, metoprolol, timolol and propranolol (to
treat high blood pressure)
• digitoxin or eplerenone (to treat certain heart conditions)
• ciclosporin or tacrolimus (to prevent organ transplant rejection)
• steroids such as hydrocortisone or prednisolone
• folic acid or vitamin D (supplements)
• toremifene, gestrinone, irinotecan or etoposide (to treat some cancers)
• methadone (used in severe pain or drug addiction)
• oral contraceptives (talk to your doctor about the best method of contraception for you)
or tibolone (female hormone)
• levothyroxine (thyroid hormone)
• montelukast or theophylline (to treat asthma)
• tropisetron and aprepitant (to treat nausea and vomiting)
• memantine (to treat dementia)
• methylphenidate (to treat attention deficit disorder)
• sodium oxybate (to treat narcolepsy).
Pregnancy and breast-feeding
If your are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby,
ask your doctor or pharmacist for advice before taking Phenobarbitone tablets.
Your doctor should discuss the possible effects of Phenobarbitone tablets on the unborn
child and the risks and benefits of treatment should be considered carefully.
Check with your doctor before taking folic acid supplements as they interact with

Phenobarbitone tablets, your doctor may need to adjust your dose.
If you are taking Phenobarbitone tablets, do not breastfeed, as the medicine will pass into the
breast milk and may harm the baby.
Driving and using machines
Phenobarbital tablets may make you feel less alert than normal. Make sure you are not affected
before driving or operating machinery
Phenobarbitone Tablets contain lactose
This medicinal product contains lactose. If you have been told by your doctor that you have an
intolerance to some sugars, contact your doctor before taking this medicine
If you see another doctor or go into hospital or need a blood or urine test, let them know what
medicines you are taking as Phenobarbitone tablets may interfere with the results.
3. How to take Phenobarbitone Tablets
Always take Phenobarbitone tablets exactly as your doctor has told you. If you are not
sure, check with your doctor or pharmacist.
You are advised not to drink alcohol, check with your doctor if you have any questions.
Swallow the tablets with water at the same time each day.
• Adults: 60mg-180mg at night.
• Children: 5mg- 8mg per kg of bodyweight a day.
• Elderly: your doctor may prescribe a lower dose.
If you take more Phenobarbitone Tablets than you should
If you (or someone else) swallow a lot of tablets at the same time, or you think a child may have
swallowed any, contact your nearest hospital casualty department or tell your doctor immediately.
Signs of an overdose include drowsiness, depression, low body temperature, speech problems,
jerky movements, jerky eye movements, loss of inhibition, reduced reflex response, low body
temperature, low blood pressure and breathing problems.
If you forget to take the tablets
Do not take a double dose to make up for a forgotten dose. If you forget to take a dose take it as
soon as you remember it and then take the next dose at the right time.
If you stop taking the tablets
If you stop taking the tablets you may develop withdrawal effects such as sleeplessness, anxiety,
tremor, dizziness, feeling sick, fits and delirium.
4. Possible side effects
Like all medicines, Phenobarbitone tablets can cause side effects, although not everybody gets
Tell your doctor if you notice any of the following side effects or notice any other effects not
• Allergic reaction: skin rash, fever, swelling of the face, lips, tongue or throat, or difficulty
breathing or swallowing.

• Blood: altered numbers and types of blood cells, if you notice increased bruising, nosebleeds,
sore throats or infections, you should tell your doctor who may want to perform a blood test.
• Metabolism and nutrition: bone softening and bone disease.
There have been reports of bone disorders including osteopenia and osteoporosis (thinning of the
bone) and fractures. Check with your doctor or pharmacist if you are on long-term anti-epileptic
medication, have a history of osteoporosis, or take steroids.
• Mental health: restlessness and confusion in the elderly, unusual excitement, depression,
memory impairment, hallucinations.
• Nervous system: hyperactivity, behavioural disturbances in children, jerky movements, jerky
eye movements, drowsiness, lethargy.
• Heart: low blood pressure.
• Lungs: difficulty breathing.
• Liver: inflammation of the liver (hepatitis), damaged bile system (cholestasis). Seen as
yellowing of skin and whites of eyes.
• Kidneys: changes in the amount or need to pass water.
• Skin: rashes, erythema multiforme (circular, irregular red patches), lumps in the armpits or
groin area. Potentially life-threatening skin rashes (Stevens-Johnson syndrome -severe skin rash
with flushing, fever, blisters or ulcers and toxic epidermal necrolysis -severe rash involving
reddening, peeling and swelling of the skin that resembles severe burns) have been reported very
rarely (see section 2),

Reporting of side effects
If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible
side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card
Scheme at:
By reporting side effects you can help provide more information on the safety of this medicine.
5. How to store Phenobarbitone Tablets
• Keep out of the sight and reach of children. Store in a cool, dry place.
• Do not use Phenobarbitone tablets after the expiry date stated on the label/carton/bottle. The
expiry date refers to the last day of that month.
• Medicines should not be disposed of via wastewater or household waste. Ask your
pharmacist how to dispose of medicines no longer required. These measures will help to
protect the environment

6. Contents of the pack and other information
What Phenobarbitone tablets contain
• The active substance is Phenobarbitone (phenobarbital).
Each tablet contains 15 mg, 30mg or 60mg of the active substance.
• The other ingredients are lactose, magnesium stearate, maize starch.
What Phenobarbitone tablets look like and contents of the pack
Phenobarbitone Tablets are white, uncoated tablets.
Pack sizes: Bottle: 28, 30, 42, 50, 56, 60, 84, 90, 100, 112, 250, 500 or 1000 tablets
Blister: 28, 30, 42, 56, 60, 84, 90 or 112 tablets
Not all pack sizes are marketed
Marketing Authorisation Holder and Manufacturer
Name and address: Bristol Laboratories Limited,
Unit 3, Canalside, Northbridge road,
Berkhamsted, Hertfordshire,
HP4 1EG, United Kingdom.
Telephone: 0044 (0) 1442 200922
Fax: 0044 (0) 1442 873717
Phenobarbitone 15mg Tablets; PL 17907/0511
Phenobarbitone 30mg Tablets; PL 17907/0512
Phenobarbitone 60mg Tablets; PL 17907/0513
The leaflet was last revised in September 2016.
To request a copy of this leaflet in Braille, large print or audio format, please contact the licence
holder at the address (or telephone, fax, email) above.

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Further information

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