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Active substance(s): DANTROLENE SODIUM

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Dantrium® 100mg Capsules


(Dantrolene sodium)
Package Leaflet: Information for the user
The name of your medicine is Dantrium 100 mg Capsules but will
be referred to as Dantrium Capsules throughout this leaflet.
Dantrium is also available in other strength of 25 mg.
Read all of this leaflet carefully before you start taking this
- Keep this leaflet. You may need to read it again.
- If you have any further questions, ask your doctor or
- 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
In this leaflet:
1. What Dantrium Capsules are and what they are used for
2. Before you take Dantrium Capsules
3. How to take Dantrium Capsules
4. Possible side effects
5. How to store Dantrium Capsules
6. Further information
Dantrium Capsules contain the active substance dantrolene
sodium – this is a muscle relaxant which is used to treat severe,
long term muscle stiffness (spasticity) in adults.

Taking Dantrium Capsules with food and drink
Avoid taking alcohol with this medicine as it may make you feel
dizzy or drowsy.
Pregnancy and breast-feeding
Do not take the capsules if pregnant or breast-feeding unless
advised otherwise by your doctor.
Ask your doctor or pharmacist for advice before taking any
Driving and using machines
Dantrium Capsules may cause drowsiness or dizziness. These
symptoms may be intensified if you have consumed alcohol.
Do not take the capsules without talking to your doctor if you
drive or are involved in hazardous activities.
Important information about some of the ingredients of
Dantrium Capsules
Lactose monohydrate - if you know you have an intolerance to
some sugars, speak to your doctor before taking this medicine.
Wheat starch – suitable for people with coeliac disease. Patients
with wheat allergy (different from coeliac disease) should not take
this medicine.
Always take Dantrium Capsules exactly as your doctor has told
you. You should check with your doctor or pharmacist if you are
not sure.
Your doctor will want to make sure that the capsules do not affect
your liver. This will mean having blood tests before you start and
while you are taking them.

DO NOT take Dantrium Capsules if you:
- are allergic to any of the ingredients in the product (see
Section 6 and end of Section 2)
- have a known liver function impairment
- have acute skeletal muscle spasms (your muscles go rigid
- need spasticity to stand up, walk or cope with daily activities.

Adults and Elderly:
Dantrium Capsules are to be taken by mouth. Swallow the
capsule with a glass of water.
The dose will vary from person to person.
- The starting dose is usually one 25mg capsule a day.
- If there is no improvement, your doctor may increase your
dose every week until the right dose for you is reached.
- The normal maximum dose is one 100mg capsule four times
a day. It is important to take the lowest dose which works
for you.
- If there is no improvement after about 6-8 weeks, your
medication will be stopped by your doctor.

DO NOT give Dantrium Capsules to children.

Children should NOT be given Dantrium Capsules.

Take special care with Dantrium Capsules if you:
- have heart or lung function impairment
- have liver disorders or notice signs or symptoms of liver
toxicity (e.g. discoloured faeces, intense itching, jaundice,
anorexia, nausea, vomiting during therapy) - contact your
doctor immediately
- are elderly.
Liver function tests should be performed frequently before start
and during Dantrium Capsules therapy as the risk of liver toxicity
appears to be greater in:
- females
- patients over 30 years old
- patients taking other medication
- females using oral oestrogen contraception.
Taking other medicines
Please tell your doctor if you are taking or have recently taken
any other medicines, including medicines obtained without a
Talk to your doctor before taking Dantrium Capsules if you are
already taking:
- Oestrogen (found in most oral contraceptive pills and
hormone replacement therapy) or other drugs which might
affect the liver.
- Tranquillisers (e.g., diazepam, lorazepam or temazepam).
- Medicines used to treat abnormal heartbeat, angina or high
blood pressure (e.g. products containing verapamil)
- Products normally used to help doctors anaesthetise patients
(e.g. products containing vecuronium).

If you take more Dantrium Capsules than you should
Do not exceed the recommended dose.
If you take too much medicine, tell your doctor immediately or go
to your nearest Accident & Emergency Department (take the
pack with you if possible).
If you forget to take Dantrium Capsules
If you miss a dose, do not take a double dose to make up for a
forgotten capsule; continue taking your medicine as normal at the
correct time.
If you have any further questions on the use of this product, ask
your doctor or pharmacist.
Like all medicines, Dantrium Capsules can cause side effects,
although not everybody gets them.
You may suffer an allergic reaction, symptoms of which
include rash, itching, difficulty in breathing or swelling of the
face, lips, throat or tongue. If this happens to you, stop
taking the capsules immediately and seek urgent medical

The following side effects have also been reported:
Most common side effects
- dizziness, drowsiness
- weakness, tiredness
- feeling generally unwell
- diarrhoea - if severe diarrhoea occurs, your doctor may stop
the capsules for a short while. If you start taking them again
and the diarrhoea returns, Dantrium Capsules is usually
stopped permanently.
Less common side effects
- loss of appetite (anorexia)
- seizures
- speech or visual disturbance
- headache
- inflammation of the membrane around the heart, sometimes
accompanied by fluid in the lungs
- feeling sick (nausea, vomiting)
- abdominal pain
- liver toxicity (characterised by inflammation of the liver),
problems with liver function
- skin rash, acne
- fever, chills.
Rare side effects
- confusion, nervousness
- depression
- difficulty sleeping (insomnia)
- fast heartbeat
- worsening of heart problems
- unstable blood pressure
- difficulty in breathing
- difficulty in swallowing
- constipation (which may on rare occasions lead to a blockage
in bowel movement)
- sweating
- increased urinary frequency
- tiny crystals or traces of blood in the urine, difficulty in
controlling the bladder (incontinence), being unable to pass
urine easily
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.
Keep out of the sight and reach of children.
Do not store above 30ºC.
Do not take the capsules after the expiry “exp” date printed on
the label. The expiry date refers to the last day of the month.
If your capsules become discoloured or show any other signs of
deterioration, consult your pharmacist who will tell you what to do.
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 Dantrium Capsules contain
The active substance is: dantrolene sodium.
Each capsule contains 100mg of dantrolene sodium.
The other ingredients are: lactose monohydrate, wheat starch,
talc, magnesium stearate, gelatine, erythrosine (E127), iron oxide
(E172) and titanium dioxide (E171) – (see also end of Section 2
“Important information about some of the ingredients of Dantrium

What Dantrium Capsules looks like and contents of the pack
- 100mg: capsules with an orange body and orange cap
containing a deep orange powder with no markings.
Dantrium 100mg Capsules are available in blister pack of 30
Manufacturer and Product Licence Holder
Manufactured by
Merck, S.L., Poligono Merck - 08100 Mollet Del Valles
(Barcelona), Spain.
FAMAR L'Aigle - Zone Industrielle n 1- Route de Crulai - 61300
L'Aigle, France.
Procured from within the EU by Product Licence holder Star
Pharmaceuticals Ltd, 5 Sandridge Close, Harrow, HA1 1XD.
Repackaged by Servipharm Ltd.

Dantrium 100mg Capsules – PL 20636/0713

Leaflet revision and issue date (Ref) 23.02.16[15]
Dantrium is a trademark of SpePharm IP, B.V.

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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.