Active substance: PHENYTOIN SODIUM

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Read all of this leaflet carefully before you start using this
• 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. 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 effects not
listed in this leaflet, please tell your doctor or pharmacist.
In this leaflet:
1. What Phenytoin Capsules are and what they are used for
2. Before you take Phenytoin Capsules
3. How to take Phenytoin Capsules
4. Possible side effects
5. How to store Phenytoin Capsules
6. Further Information

The name of your medicine is Phenytoin sodium NRIM 100mg Capsules
(referred to as Phenytoin Capsules or as Phenytoin throughout this leaflet).
Phenytoin belongs to a group of medicines called anti-epileptic drugs; these
medicines are used to treat epilepsy.
Phenytoin can be used to control a variety of epileptic conditions, to control
or prevent seizures during or after brain surgery or severe head injury.
Phenytoin can also be used to treat trigeminal neuralgia (facial nerve pain).
You should ask your doctor if you are unsure why you have been given
Phenytoin capsules.


- Medicines used to treat fungal infections (e.g. amphotericin B, fluconazole,
itraconazole, ketoconazole and miconazole).
- Medicines used for tuberculosis and other infections (chloramphenicol,
isoniazid, rifampicin, sulphonamides, doxycycline, ciprofloxacin and
- Medicines used for stomach ulcers (omeprazole, sucralfate, the
medicines known as H2 antagonists e.g. cimetidine, ranitidine, famotidine
and some antacids).
- Medicines used for asthma and bronchitis (theophylline).
- Medicines used for pain and inflammation (phenylbutazone, salicylates
e.g. aspirin and steroids).
- Medicines used for sleeplessness, depression and psychiatric disorders
(chlordiazepoxide, clozapine, diazepam, disulfiram, fluoxetine,
methylphenidate, paroxetine, phenothiazines, trazodone, tricyclic
antidepressants and viloxazine).
- Medicines used for diabetes (tolbutamide).
- Some hormone replacement therapies (oestrogens), oral contraceptives
(the birth control pill).
- Medicines used for organ and tissue transplants, to prevent rejection
- Medicines used for cancer (antineoplastic agents).
- Muscle relaxants used for surgery (neuromuscular blockers), some
anaesthetic drugs (halothane) and methadone.
- Some products available without a prescription (folic acid, theophylline,
vitamin D).
Your doctor may need to test the amount of Phenytoin in your blood to help
decide if any of these medicines are affecting your treatment.

You should not take Phenytoin until you are sure it is safe for you to do so.

Please tell your doctor or pharmacist if you are taking or have recently taken
any other medicines, including medicines obtained without a prescription.

Do not take Phenytoin
- if you are allergic (hypersensitive) to phenytoin, other hydantoin products
or any of the other ingredients of Phenytoin capsules.

The herbal preparation 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.

Take special care with Phenytoin
Medicines are not always suitable for everyone. Your doctor needs to know
before you take phenytoin if you suffer from or have suffered in the past
from any of the following conditions:
- Liver disease.
- Porphyria (an inherited disease that affects haemoglobin biosynthesis).

Phenytoin capsules may also interfere with certain laboratory tests that you
may be given.

A small number of people being treated with antiepileptics such as
phenytoin sodium have had thoughts of harming or killing themselves. If at
any time you have these thoughts, immediately contact your doctor.
Serious skin side effects can rarely occur during treatment with Phenytoin.
This risk may be associated with a variant in genes in a subject with Chinese
or Thai origin. If you are of such origin and have been tested previously
carrying this genetic variant (HLA-B*1502), discuss this with your doctor
before taking Phenytoin.

If you are not sure if any of the above applies to you, talk to your doctor or
pharmacist before taking Phenytoin.
Taking Phenytoin with food or drink
Phenytoin can be taken before or after food and drinks. Drinking a lot of
alcohol can also affect the concentration of Phenytoin in your blood.
Pregnancy or breast-feeding
If you think you might be pregnant, or are planning to get pregnant, tell your
doctor before you take Phenytoin.
You should not take phenytoin if you are breast-feeding.
Ask your doctor or pharmacist for advice before taking any medicine.

Taking other medicines
Some medicines can affect the way Phenytoin works, or Phenytoin itself
can reduce the effectiveness of other medicines taken at the same time.
These include:
- Medicines used for heart and circulation problems (dicoumarol, digitoxin,
amiodarone, furosemide, quinidine, reserpine, warfarin, and calcium
channel blockers e.g. diltiazem and nifedipine).
- Medicines used for epilepsy (carbamazepine, lamotrigine, phenobarbital,
sodium valproate and valproic acid, succinimides e.g. ethosuximide and

Driving and using machines
Phenytoin may cause dizziness or drowsiness, especially during the first few
weeks of treatment. If you experience these symptoms, do not drive or
operate tools or machinery or carry out other hazardous activities.
Important information about some of the ingredients of Phenytoin
Phenytoin contains lactose, a type of sugar. If you have been told that you
have an intolerance to some sugars, contact your doctor before taking this
medicinal product.

Always take Phenytoin exactly as your doctor has told you. You should check
with your doctor if you are not sure.
It is best to take Phenytoin at the same time each day.
Swallow the capsules whole, with plenty of water.
The amount of Phenytoin needed varies from one person to another. Most
adults need between 200mg and 500mg a day either as a single or divided
dose. Occasionally higher doses are needed.
Infants and children usually start on a dose that depends on their weight
(5mg per day for every kg they weigh) and is given as a divided dose, twice
a day. The dose is then adjusted up to a maximum of 300mg a day.
The dose of Phenytoin for elderly patients who may be taking other
medicines may also need careful consideration and adjustment by their
If you take more Phenytoin than you should
Phenytoin is dangerous in overdose. If you or someone else accidentally
takes too much phenytoin contact your doctor at once or go to the nearest
hospital casualty department. Always take the labelled medicine package
with you, whether there is any Phenytoin left or not, as this will allow easier
identification of the medicine.
If you forget to take Phenytoin
If you forget to take a dose, take it as soon as you remember unless it is time
for your next dose. Do not take a double dose to make up for a missed dose.
If you stop taking Phenytoin
Do not stop taking phenytoin unless your doctor tells you to. If you suddenly
stop taking this medicine you may have a seizure. Should you need to stop taking
phenytoin, your doctor will have decided which the best method is for you.
If you have any further questions on the use of this product, ask your doctor
or pharmacist.

Like all medicines, Phenytoin can cause side effects although not everybody
gets them.
Tell your doctor immediately if you experience any of the following
symptoms after taking this medicine. Although they are very rare, these
symptoms can be serious.
- Sudden wheeziness, difficulty in breathing, swelling of eyelids, face or lips,
rash or itching (especially affecting the whole body).
- If you develop a severe skin rash that causes blistering, (this can also
affect the mouth and tongue). These may be signs of a condition known
as Stevens Johnson Syndrome, or toxic epidermal necrolysis (TEN). Your
doctor will stop your treatment in these cases.
- If you notice bruising, fever, you are looking pale or you have a severe
sore throat. These may be the first signs of an abnormality of the blood,
including decreases in the number of red cells, white cells or platelets.
Your doctor may take regular blood samples to test for these effects.
- Skin rash and fever with swollen glands, particularly in the first two
months of treatment, as these may be signs of a hypersensitivity reaction.
If these are severe and you also experience pain and inflammation of the
joints this could be related to a condition called systemic lupus
- If you experience confusion or have a severe mental illness, as this may
be a sign that you have high amounts of phenytoin in your blood. On rare
occasions, when the amount of phenytoin in the blood remains high,
irreversible brain injury has occurred. Your doctor may test your blood to
see how much phenytoin is in the blood and may change your dose.

Other side-effects that may occur are:
- Effects on your nervous system: Unusual eye movements,
unsteadiness, difficulty in controlling movements, shaking, abnormal
or uncoordinated movements, slurred speech, confusion, pins and
needles or numbness, drowsiness, dizziness, vertigo, sleeplessness,
nervousness, twitching muscles, headaches.
- Effects on your skin: skin rash including measles-like reactions
which are mild.
- Effects on your stomach and intestines: feeling sick, being sick
and constipation.
- Effects on your blood and lymph system: swelling of the lymph
- Effects on your liver and kidney: inflammation of the kidneys and
liver, liver damage (seen as yellowing of the skin and whites of the eye).
- Effects on your reproductive system and breasts: changes in
the shape of the penis, painful erection.
- Effects on your hands, face and body: changes in the hands with
difficulty in straightening the fingers, changes in facial features, enlarged
lips or gums, increased or abnormal body or facial hair.
- Effects on your respiratory system: problems breathing,
inflammation of the lining of the lung.
- Effects on your immune system: problems with the body’s defence
against infection, inflammation of the wall of the arteries.
- Effects on medical tests: increased levels of blood sugar, or
decreased levels of blood calcium, folic acid and vitamin D. If you also do
not get enough vitamin D in your diet or from exposure to sunlight, you
may suffer from bone pain or fractures.
- 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 get serious or lasts longer than a few days, or if you
notice other unwanted effects, tell your doctor or pharmacist.

• Keep out of the reach and sight of children.
• Do not use Phenytoin after the expiry date, which is printed on the end
of the carton and also on the bottle label. The expiry date refers to the last
day of the month.
• Do not store above 25ºC. Store in the original package. Keep the container
tightly closed in order to protect from light and moisture
• 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 Phenytoin Capsules contain
The name of this medicine is Phenytoin sodium NRIM 100mg Capsules. The
active substance in your capsules is phenytoin sodium. Each hard capsule
contains 100mg of the active ingredient phenytoin sodium. Other ingredients
include lactose monohydrate and magnesium stearate. The capsule shell is
made of gelatin, water, erythrosine (E127), quinoline yellow (E104), titanium
dioxide (E171), sodium lauril sulfate and black edible printing ink, which
contains shellac, propylene glycol, black iron oxide (E172) and potassium
What Phenytoin Capsules look like and contents of the pack
Phenytoin sodium NRIM 100mg Capsules are hard gelatin capsules with an
orange transparent coloured cap printed with “146” and white coloured
body, containing white granular powder. Phenytoin sodium NRIM 100mg
Capsules are supplied in a HDPE capsule container with a child-resistant
polypropylene cap. Each bottle contains 84 capsules.
Marketing Authorisation Holder and Manufacturer
The Marketing Authorisation holder and manufacturer of these capsules is
NRIM Limited, Unit 15 Moorcroft, Harlington Road, Hillingdon, UB8 3HD,
United Kingdom.
This leaflet was prepared in 03/2013


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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.