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Physeptone Injection 25mg/ml
Methadone Hydrochloride


Read all this leaflet carefully before you are given
Physeptone Injection
• Keep this leaflet. You may need to read it again
• If you have any further questions, please ask your doctor or
• 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 nurse
In this leaflet:
1. What Physeptone Injection is and what it is used for
2. Before Physeptone Injection is given
3. How Physeptone Injection is given
4. Possible side effects
5. Storing Physeptone Injection
6. Further information
This leaflet contains a summary of the information available for
this medicine. You should ask your doctor or nurse if you are
unsure about any aspect of this medicine.

1. What Physeptone Injection is and what it is
used for
The active ingredient Methadone Hydrochloride is a synthetic
opiate (a morphine-like drug) used in the treatment of addiction
in order to reduce withdrawal symptoms.

2. Before you are given Physeptone Injection
You should not be given Physeptone Injection if:
• you are allergic (hypersensitive) to methadone or any of the
ingredients of this medicine (listed in section 6)
• you are taking or have recently stopped taking a type of
medicine known as Monoamine Oxidase Inhibitors (MAOIs)
which are used to treat depression
• you have any problems with your breathing or any chronic
lung disease such as chronic obstructive pulmonary disease
• you are having an asthma attack. Do not take your dose until
you have completely recovered
• you are not already receiving methadone. This is a high
concentration and is not suitable for people who have not
taken methadone before
• you are suffering from a problem that could cause paralysis
of the small intestine (paralytic ileus)
• you are suffering from problems with your bowel, such as an
inflammatory bowel disorder
Physeptone Injection is not suitable for children.
Take special care with Physeptone Injection
Tell your doctor if:
• you have history of asthma or breathing difficulties
• you have bowel problems
• you have liver or kidney problems
• you have a history of low blood pressure
• you have a history of under-active thyroid gland, or problems
with your adrenal glands
• you have a history of enlarged prostate gland
• you have condition that causes severe muscle weakness and
fatigue (myasthenia gravis)
• you are in shock
• you are at risk of developing an obstruction of the intestine
• you are suffering from alcoholism
• you are pregnant, trying for a baby, breast-feeding or are in labour

• you have a type of cancer of the adrenal glands known as
If you are elderly your doctor will give Physeptone Injection to
you with special care. If any of the conditions above apply to
you, please consult your doctor.
You should be aware that prolonged use of methadone can
result in tolerance of the drug and both physical and
psychological addiction to methadone. If you have any concerns
speak to your doctor before you are given this medicine.
Physeptone Injection may affect the electrical signals which
control your heart contractions, particularly at high doses.
Tell your doctor if:
• you have history of heart problems
• you have liver disease
• you have any blood abnormalities such as low levels of
potassium or magnesium
• you have a history of sudden death in the family.
Taking other medicines
Please tell your doctor or nurse if you are taking or have
recently taken any other medicines, including medicines
obtained without a prescription.
Tell your doctor if you are taking any of the following:
• medicines used to treat addiction e.g. naltrexone and
• cimetidine (a medicine used to treat stomach ulcers)
• drugs used to treat epilepsy (e.g. phenytoin and
• naloxone (a medicine used to treat an overdose of opioid
• antibiotics (medicines used to treat bacterial infections e.g.
rifampicin, ciprofloxacin, erythromycin and rifabutin)
• antifungals (medicines used to treat fungal infections e.g.
fluconazole and ketoconazole)
• medicines that make urine more acidic or alkaline e.g.
ascorbic acid and sodium bicarbonate
• antiviral drugs including some medicines used to treat HIV
e.g. nevirapine, zidovudine, efavirenz, nelfinavir, ritonavir and
• metoclopramide or domperidone (medicines used to treat
nausea and vomiting)
• mexiletine (a drug used to treat heart irregularities)
• medicines used to treat depression including fluvoxamine,
fluoxetine and tricyclic antidepressants or MAOIs
• CNS depressants (medicines that act on the brain and cause
drowsiness or sleepiness e.g. barbiturates, benzodiazopines,
chloral hydrate and chlormethiazole)
• other opioid type drugs e.g. pethidine
• pentazocine (a pain killer)
• atropine (a medicine used to treat heart problems)
• cyclizine (an antihistamine used to treat nausea, vomiting
and dizziness)
Other medicines you may be taking can also affect the heart.
You must tell your doctor about any other medicines that you
are taking as they may be dangerous if they are taken with
methadone. In these situations your doctor may decide that it is
necessary to monitor your heart with an electrocardiogram (ECG)
at the start of treatment to ensure that these effects do not occur.
Continued overleaf

Receiving Physeptone Injection with food and drink
You must not drink alcohol whilst you are being treated with
Physeptone Injection as this could cause serious side effects.
You are advised not to drink grapefruit juice whilst you are being
treated with Physeptone Injection as it could cause an overdose.
Pregnancy, breast-feeding and labour
Physeptone Injection should not be given during labour. If you
are pregnant or breast-feeding you should discuss this with
your doctor before being given Physeptone Injection.
Driving and using machinery
The ability to drive or operate machinery may be severely
affected during and after treatment with methadone. You
must not drive or use machinery until you are told that you
can do so by your doctor.
The medicine can affect your ability to drive as it may make
you sleepy or dizzy.
• Do not drive while taking this medicine until you know how
it affects you.
• It is an offence to drive if this medicine affects your ability to
• However, you would not be committing an offence if:
• The medicine has been prescribed to treat a medical or
dental problem and
• You have taken it according to the instructions given by
the prescriber or in the information provided with the
medicine and
• It was not affecting your ability to drive safely
Talk to your doctor or pharmacist if you are not sure whether it
is safe for you to drive while taking this medicine.

3. How Physeptone Injection is given
Physeptone Injection will be given to you by a doctor in a
hospital. It will be given under the skin, into the vein or into a
The usual initial dose is 10-20mg a day. The dose will be slowly
increased by 10-20mg until you show no signs of withdrawal or
intoxication. The dose may need to be over 100mg daily
(depending of the level of tolerance you have to Physeptone) in
order to prevent withdrawal symptoms.
Elderly or ill:
If you are elderly or ill, your doctor will only prescribe repeated
doses with caution.
Not recommended. There is a serious risk of poisoning.
Remember to keep your medicine safely where children can not
get it.
If you think you have been given too much Physeptone
This medicine will be given to you by your doctor so it is
unlikely you will receive too much. If you are concerned about
your treatment, please talk to your doctor. If you are given too
much Physeptone Injection, you can experience the following:
• difficulty in breathing
• extreme sleepiness, fainting or coma
• pin point pupils
• muscle weakness
• cold and clammy skin
• slow heartbeat, low blood pressure, heart attack or shock. In
severe cases death may occur.
In the event of overdose you should seek medical assistance
immediately even if you feel well as you may be suffering
methadone poisoning.

4. Possible side effects
Like all medicines, Physeptone Injection can cause side effects,
although not everybody gets them.
Repeated use of methadone can result in tolerance and
Side effects which may occur include:
• dizziness (including vertigo), drowsiness, hallucinations
• nausea (feeling sick) or vomiting (being sick), constipation, a
dry mouth
• headaches, raised pressure in the brain
• rashes or itching
• sweating
• reduced blood pressure (you may feel dizzy on standing up)
• pin point pupils
• confusion, mood changes
• fast or slow beating of the heart, a feeling of trembling in the
• facial flushing
• spasms of the tubes from the gall bladder or urinary bladder
• difficulty in passing water
• a reduction in sex drive
• a reduction in body temperature
• redness, swelling and hardening of the skin at the site of the
• painful menstrual cramps or absence of period.
If any of the side effects becomes serious or you notice side
effects not listed in this leaflet please contact your doctor or

5. Storing Physeptone Injection
Keep out of the reach and sight of children.
This medicine has an expiry date on the ampoule label and
carton. Your doctor or nurse will check that this medicine has
not passed the expiry date before it is given to you.
Store below 25°C and protect from light.

6. Further Information
What Physeptone Injection contains:
The active ingredient is Methadone Hydrochloride 25mg in 1ml.
The other ingredient is water for injections.
What Physeptone Injection looks like and the contents of
the pack:
Physeptone Injection is a clear colourless solution supplied in
clear glass ampoules, each containing 2ml of solution packed
into a cardboard carton. Each pack contains 10 ampoules.
Marketing Authorisation Holder and Manufacturer:
Martindale Pharmaceuticals, Bampton Road, Harold Hill, Essex
Product licence number: PL 01883/0063
Date of Revision: January 2014
If this leaflet is difficult to see or read, please contact the
marketing authorisation holder for help.


100mm Measurement Verification Bar

Component Code: D02751
Paper size: 170 x 220mm
Version Control Date


Version A Created 21/01/14 HM
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Grand Fromage Creative Limited
Amherst House, 22 London Road
Riverhead, Sevenoaks, Kent, TN13 2BT, UK
t: 01732 456 187

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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.