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Active substance(s): PHENOBARBITAL

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Read all of this leaflet carefully before you start taking this medicine.
• Keep this leaflet. You may need to read it again.
• Ask your pharmacist if you need more information or advice.
• This medicine has been prescribed for you. Do not pass it on to others. It may harm them, even if their symptoms are the same
as yours.
• If any of the side effects gets serious, or if you notice any side effect not listed in this leaflet, please tell your doctor or
Phenobarbital Activase tablets will be referred to as Phenobarbital Tablets throughout this leaflet.
In this leaflet:
1. What Phenobarbital Tablets are and what they are used for
2. Before you take Phenobarbital Tablets
3. How to take Phenobarbital Tablets
4. Possible side effects
5. How to store Phenobarbital Tablets
6. Further information
The name of your medicine is Phenobarbital Tablets. It contains the active ingredient Phenobarbital. Phenobarbital belongs to a
group of drugs known as barbiturates. In an epileptic fit excessive electrical activity builds up in the brain. Phenobarbital works by
neutralizing this excessive electrical activity.
It is used for the treatment of epilepsy (brain disorder that causes people to have recurring seizures) but not for absence seizures.
Do not take Phenobarbital Tablets if you:
• are allergic (hypersensitive) to barbiturates or to any of the other ingredients of Phenobarbital Tablets. See section 6.
• suffer from acute intermittent porphyria (genetic disorder)
• suffer from severe respiratory depression (difficulty breathing)
• are suffering from severe liver and kidney problems.
Take special care with Phenobarbital Tablets
Please consult your doctor or pharmacist before taking this medicine if you:
• are feeling weak or feeble
• are mentally or physically infirm
• have kidney problems
• have liver problems
• have breathing difficulty
Effects on laboratory tests
Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body’s response to
Phenobarbital Tablets.
Taking other medicines
You should tell your doctor if you are taking or have taken any of the following medicines as they may interact with your Phenobarbital
Examples of medicines that can affect Phenobarbital Tablets are:
• Warfarin – anticoagulants to thin the blood
• Chloramphenicol, an antibiotic used to treat eye and ear infections
• Griseofulvin used to treat fungal infections of the skin
• Steroids including oral contraceptives

Ciclosporin which is used in organ and tissue transplants.
Phenytoin, Lamotrigine, Carbamazepine and Sodium Valproate to treat epilepsy
Phenylbutazone to treat a painful condition of the spine
Rifampicin to treat tuberculosis
Phenothiazines to treat psychiatric disorders
Amitriptyline, Imipramine to treat depression
Nifedipine, Felodipine, Verapamil or Nimodipine to treat heart problems
Theophylline to help your breathing
Thyroxine to treat a disorder of the thyroid gland
The herbal remedy St John’s Wort (Hypericum Perforatum) should not be taken at the same time as this medicine. If you
already take St John’s Wort, consult your doctor before stopping the St John’s Wort preparation.
• Indinavir or Saquinavir – antiviral medicines used in the treatment of HIV
• Disopyramide, Quinidine and Digitoxin to treat heart problems
• Folic acid in high doses.
Please tell your doctor or pharmacist if you are taking or have recently taken any other medicines, including medicines obtained
without prescription.

Taking Phenobarbital Tablets with food and alcohol
Do not drink alcohol while you are taking Phenobarbital.
Pregnancy and breast-feeding
If you are pregnant or planning to become pregnant you should speak to your doctor before taking Phenobarbital. If you become
pregnant whilst taking Phenobarbital Tablets, your doctor will decide if you should continue taking this medicine or whether another
would be more suitable during pregnancy. Do not stop taking Phenobarbital until you have seen your doctor as it is important to
control your fits. If taken during pregnancy (particularly in the first 3 months and the last 3 months) Phenobarbital may cause birth
defects. It may also cause problems with bleeding in your baby when it is born. However, your doctor may decide that it is very
important that you continue taking Phenobarbital. Your doctor will explain the risks to you. As with all women, adequate supplements
of folic acid should be taken before conception and during pregnancy.
As Phenobarbital is released into breast milk this may make your baby sleepy and therefore breast feeding is not advisable.
Driving and using machines
Phenobarbital Tablets may make you drowsy or affect your concentration. Do not drive or use any tools or machines if you are
affected in this way and do not drink alcohol, as this will make these effects worse.
Important information about some of the ingredients of Phenobarbital Tablets
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 medicinal product.
Also contains Sunset Yellow (E110). May cause allergic reactions.
Always take Phenobarbital Tablets exactly as your doctor has told you. You should check with your doctor or pharmacist if you are
not sure. The number of tablets you will take will depend on what you are taking the tablets for. Your doctor will probably start you
on a low dose of Phenobarbital Tablets and gradually increase your dose.
Dosage – You should swallow the tablets whole with a glass of water.
Adults: The usual dose is 60 to 180 mg daily, taken at night.
Children: If this medicine is prescribed for a child make sure that the tablets are taken as stated on the pharmacist’s label. The usual
dose is 5 to 8 mg per kg of bodyweight per day.
If you take more Phenobarbital Tablets than you should
If you take more Phenobarbital Tablets than you should, contact your doctor or nearest hospital emergency department immediately.
Take the pack and remaining tablets with you.
If you forget to take Phenobarbital Tablets
If you forget to take a dose, take it as soon as you remember unless it is almost time for your next dose. Do not take a double dose
to make up for a forgotten tablet.

If you stop taking Phenobarbital
Do not stop taking Phenobarbital Tablets without talking to your doctor. It may take a few weeks or longer before you feel the full
benefit of Phenobarbital. Continue to take Phenobarbital even if you feel well.
Like all medicines, Phenobarbital Tablets can cause side effects, although not everybody gets them.
Very serious side effects – If any of the following happens, stop taking Phenobarbital Tablets and tell your doctor
immediately or go to the nearest hospital emergency department:
Rare allergic (hypersensitive) reactions such as difficulty of
• breathing, swelling of your face, throat or tongue, skin rash, itching, hives, blisters, or a scaly skin.
If you experience any of the following side effects please tell your doctor or pharmacist.
Very common (occurring in more than 1 in 10 patients)
• rash or skin eruptions
• a yellowing of your skin or the whites of your eyes.
The following side effects are usually mild and may disappear with continued treatment. If they are severe or last longer
than a few days you should tell your doctor:
• drowsiness or lack of energy
• memory disturbances, difficulty in concentrating
• depression
• unsteady walking
Other side effects which may occur are:
• changes in behaviour
• difficulty breathing
• anaemia
• visual disorders
• osteomalacia – an abnormal softening of bone
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 antiepileptic medication, have a history of osteoporosis, or take steroids.
If any of the side effects gets serious, or if you notice any side effects not listed in this leaflet, please tell your doctor or pharmacist.
Keep out of the reach and sight of children.
Do not store the tablets above 25°C. Store in the original container. Keep the container tightly closed.
Do not take these tablets after the expiry date shown on the pack. 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.
What Phenobarbital 30mg Tablets contain:
White, circular tablets. Each tablet contains 30 mg of Phenobarbital, the active ingredient.
Phenobarbital Activase 30mg Tablets were previously known as Phenobarbitone Tablets BP.
The tablets also contain the inactive ingredients Maize Starch, Lactose Monohydrate, Sodium Lauryl Sulfate, Sodium Starch
Glycolate (Type A), Magnesium Stearate and Stearic Acid.
Phenobarbital Tablets are available in packs of 28 and 1000 tablets. Not all pack sizes may be marketed.
Marketing Authorisation Holder
Activase Pharmaceuticals Limited, 11 Boumpoulinas, 3rd Floor, P.C. 1060 Nicosia, Cyprus

LPC Medical (UK) Limited, 30 Chaul End Lane, Luton, Bedfordshire, LU4 8EZ, U.K.
This leaflet was last revised in December 2013

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Source: Medicines and Healthcare Products Regulatory Agency

Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.