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4. Possible side effects

6. Further Information

Like all medicines Phenobarbital Injection can cause side effects,
although not everybody gets them.

What Phenobarbital Injection contains
The active ingredient is Phenobarbital Sodium.

1. What Phenobarbital Injection is and what it is used for
2. Before Phenobarbital Injection is given
3. How Phenobarbital Injection will be given
4. Possible side effects
5. How to store Phenobarbital Injection
6. Further information

• Digitoxin, quinidine, disopryamide (drugs used to treat
certain heart disorders)
• Griseofulvin (a drug used to treat certain fungal infections)
• Phenylbutazone (an anti-inflammatory drug)
• Rifampicin (used in the treatment of TB)
• Systemic steroids including oral contraceptives (birth control),
possibly leading to contraceptive failure
• Theophylline (used to treat asthma)
• Thyroxine (used to treat an under active thyroid)
• Protease inhibitors indinavir, lopinavir, nelfinavir and
saquinavir (drugs used to treat HIV)
• Memantine (a drug used to treat Alzheimer’s disease)
• Toremifene (an anti-oestrogen used to treat certain types of
breast tumour following the menopause)
• Tropisetron (an anti-sickness drug)
• Folic acid or folinic acid
• Vitamin D
• Montelukast (a drug used to treat breathing difficulties)
• Alcohol and strong painkillers (e.g. aspirin, paracetamol)
• Tricyclic antidepressants (e.g. amitriptyline)
• Antiepileptic drugs (e.g. other barbiturates, carbamazepine,
lamotrigine, phenytoin and sodium valproate)
• Phenothiazines (mood modifiers e.g. chlorpromazine,
fluphenazine and pericyazine)
• Tranquillisers (e.g. diazepam)
• Antipsychotic drugs (e.g. haloperidol)
• St John’s wort (Hypericum perforatum) for depression
If you are in any doubt please tell your doctor of any
medication you are taking.

1. What Phenobarbital Injection is and what it is
used for

Using Phenobarbital Injection with food and drink:
You are advised NOT to drink alcohol with this medicine.

5. How to store Phenobarbital Injection

Product Licence Number:
Phenobarbital Injection 15mg/ml PL 01883/6161;
Phenobarbital Injection 30mg/ml PL 01883/6188;
Phenobarbital Injection 60mg/ml PL 01883/6189;
Phenobarbital Injection 200mg/ml PL 01883/6190; HK 45682

Keep out of the reach and sight of children.

This leaflet was last revised in: November 2012

Phenobarbital belongs to a group of drugs known as
barbiturates. Barbiturates have antiepileptic properties which
mean they help prevent some types of epileptic seizures. They
also have hypnotic properties which mean they can make you
feel sleepy.

Pregnancy and breast-feeding
This medicine should not be given to you if you are pregnant,
trying to become pregnant or are breast-feeding, unless your
doctor has specifically recommended it.
Ask your doctor or pharmacist for advice before taking any

Phenobarbital Injection should be kept in the outer carton in
order to protect from light. Do not store above 25°C.

Driving and using machinery:
This medicine may make you feel sleepy. If so, do not drive a car
or operate machinery.

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.


Phenobarbital Sodium Injection
15mg/ml, 30mg/ml, 60mg/ml or 200mg/ml
Phenobarbital Sodium
(Referred to as Phenobarbital Injection in this leaflet)

Read all of this leaflet carefully before you are given this
• Keep this leaflet. You may need to read it again.
• If you have any further questions, please ask your doctor
or pharmacist.
• 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 get serious, or if you notice any
side effects not listed in this leaflet, please tell your
doctor or pharmacist.

In this leaflet:

Phenobarbital Injection is used in the treatment of most types of
epilepsy except absence seizures (petit mal).

2. Before Phenobarbital Injection is given
You should not be given Phenobarbital Injection if:
• You are allergic (hypersensitive) to any barbiturates or any of
the ingredients of this medicine (see section 6)
• You suffer from acute intermittent porphyria (a type of blood
• You suffer from severe breathing difficulties (respiratory
• You suffer from liver or kidney problems
If your problem is not severe your doctor may decide to give you
the medicine with caution. Talk to your doctor, they will advise
you on your particular situation.
Take special care with Phenobarbital Injection if:
• You have an alcohol or drug problem
• You are pregnant, planning to become pregnant or are
• You are young, elderly or in poor health
If any of the above applies to you, please tell your doctor.
A small number of people being treated with anti-epileptics
such as Phenobarbital Injection have had thoughts of harming
or killing themselves. If at any time you have these thoughts,
immediately contact your doctor.
Using other medicines:
Please tell your doctor if you are taking or have recently taken
any other medicines, including medicines obtained without a
Please tell your doctor if you are taking any of the following
medicines which may interact with Phenobarbital Injection:
• Any calcium channel blockers (drugs that affect the way
calcium passes into certain muscle cells) e.g. diltiazem,
felodipine, verapamil, nimodipine, nifedipine
• Coumarin anticoagulants (drugs that reduce the clotting of
blood e.g. warfarin)
• Chloramphenicol, doxycycline, metronidazole, voriconozole,
telithromycin (antibiotics)
• Cyclosporin (a drug used to suppress the body’s immune

3. How Phenobarbital Injection will be given
This medicine is an injection and will be given to you by your
doctor. Your doctor will determine the dose you require.
• 50 - 200mg as a single dose
• The injection can be administered into a muscle, under the
skin or, into a vein following dilution with water
• Repeated, if necessary after 6 hours
• Use with caution
• 3 - 5mg per kg body weight as a single dose into the muscle
Your doctor will advise you on the duration of your therapy.
If you are given too much Phenobarbital Injection:
If you experience any of the following, tell your doctor
• feeling sleepy
• feeling faint
• feeling extremely cold
• your breathing becoming very shallow
If you are at all concerned that you have been given too much
of this medicine please tell your doctor.
If you missed a dose of Phenobarbital Injection:
This is not applicable because your doctor will administer this
If treatment with Phenobarbital Injection is stopped:
Stopping treatment with this medicine may result in the return
of, and increase in, seizures.
If you have any further questions on the use of this product, ask
your doctor or pharmacist.
Continued overleaf

This injection may cause:
• Breathing difficulty
• Confusion
• Loss of control of intentional movements
• Drowsiness
• Depression
• Blood disorders
• Memory impairment
• Rapid involuntary movements of the eye (Nystagmus)
• Skin reactions (though these are rare)
• Sluggishness
• Excitement and irritability
• Allergic skin reactions
• Shaky movements and unsteady walk (ataxia)
• Inflammation of the liver (hepatitis)
• Softening of bones
There have been reports of bone disorders including
osteopenia and osteoporosis (thinning of the bones) 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 get serious, or you notice any side
effects not listed in the leaflet, please tell your doctor or

Do not use Phenobarbital Injection after the expiry date which is
stated on the ampoule label. The expiry date refers to the
last day of that month. The doctor or nurse will check that the
product has not passed this date.

Phenobarbital Injection is a sterile solution.
Each 15mg/ml ampoule contains 15mg of Phenobarbital
Each 30mg/ml ampoule contains 30mg of Phenobarbital
Each 60mg/ml ampoule contains 60mg of Phenobarbital
Each 200mg/ml ampoule contains 200mg of Phenobarbital
The other ingredients are Propylene Glycol, Disodium Edetate
and Water for Injections.
What Phenobarbital Injection looks like and contents of
the pack:
Each ampoule contains 1ml of Phenobarbital Injection.
The medicine is supplied to your pharmacist or doctor in packs of
10 clear glass ampoules.
Marketing Authorisation Holder and Manufacturer:
Martindale Pharmaceuticals, Bampton Road, Harold Hill, Romford,
RM3 8UG, United Kingdom.

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.