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Pentazocine 50mg Capsules
(Pentazocine Hydrochloride)
Read all of this leaflet carefully before you start taking this medicine because it contains
important information for you.
• Keep this leaflet safe, as you may want to read it again.
• If you have any further questions, ask your doctor or pharmacist.
• This medicine has been prescribed for you only. Do not pass it onto others. It may harm them,
even if their signs of illness are the same as yours.
• If you get any side effects talk to your doctor or pharmacist. This includes any possible side
effects not listed in this leaflet. See section 4.
What is in this leaflet:
1. What Pentazocine is and what it is used for
2. What you need to know before you take Pentazocine
3. How to take Pentazocine
4. Possible side effects
5. How to store Pentazocine
6. Contents of the pack and other information
1. What Pentazocine is and what it is used for
Pentazocine belongs to a group of medicines called analgesics which act on the central nervous
system (the brain and spinal cord) to relieve moderate to severe pain.
2. What you need to know before you take Pentazocine
Do not take Pentazocine if:
• You are allergic (hypersensitive) to Pentazocine, analgesics or to any of the other ingredients of
this medicine (listed in section 6)
• You suffer from heart failure due to lung disease
• You suffer from a brain condition (including raised pressure in the skull) or head injury
• You suffer from asthma, lung disease or have breathing difficulties, especially if you have blue
discolouration of the skin (cyanosis) or cough up a lot of phlegm
• You suffer from alcoholism or are a heavy drinker
• You have porphyria (a group of rare inherited or acquired disorders where there is a problem with
the production of haem (used to make haemoglobin in red blood cells) within the body)
Warnings and precautions
Talk to your doctor before taking Pentazocine:
• Taking a pain reliever regularly for a long time may lead to a dependence (addiction)
• Taking a pain reliever too often or for too long can make headaches develop or worsen.
Headaches caused by overuse of medicine should not be treated by increasing the dose.
• If you suffer from phaeochromocytoma (untreated tumour of the adrenal gland)
• If you have suffered a recent heart attack due to increases in heart rate and blood pressure
• If you suffer from severe kidney or liver problems
• If you are elderly, as you may be especially sensitive to the effects of Pentazocine
• If you have ever suffered from drug dependency or abuse
• If you have a history of or suffer from fits or seizures
• If you take other analgesic medicines (See “Other medicines and Pentazocine”)
• If you have an underactive thyroid gland (hypothyroidism)
• If you have a condition in which the adrenal glands do not produce adequate amounts of steroid
hormones (adrenocortical insufficiency)
• If you suffer from inflammation (swelling) of the prostate (prostatic hypertrophy)
• If you suffer from inflammatory or obstructive bowel disorders
• If you suffer from swelling (inflammation) of the gallbladder (cholecystitis)
• If you suffer from inflammation of the pancreas (pancreatitis)
• If you suffer from unexplained stomach pain

You are taking medicines used to treat major depressive episodes, known as Monoamine
Oxidase Inhibitors (MAOIs) (See “Other medicines and Pentazocine”). Treatment with
Pentazocine should only be started 2 weeks after discontinuing treatment with an MAOI

Other medicines and Petanzocine
Tell your doctor or pharmacist if you are taking, have recently taken or might take any other
medicines, including those obtained without a prescription. This includes herbal medicines.
Medicines which may interact with or be affected by Pentazocine:
• Antidepressant medicines known as Monoamine Oxidase Inhibitors (MAOI) in the past 2 weeks
• Medicines which make you sleepy including:
o Phenothiazines such as Trifluoperazine, used to treat anxiety, mental disorders, feeling
and/or being sick (nausea, vomiting)
o Tricyclic antidepressants, used to treat depression such as amitriptyline
o Medicines used to improve breathing ability such as doxapram (respiratory stimulants)
• Tobacco smoking may decrease the effectiveness of Pentazocine
• Strong pain relievers such as diamorphine (heroin), morphine and naloxone
Taking Pentazocine with food and drink and alcohol
• These capsules should be taken after meals
• Do not drink alcohol while you are taking these capsules. If you drink alcohol whilst taking this
medicine the sedative effect may be enhanced.
Pregnancy and breast-feeding
If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask
your doctor or pharmacist for advice before taking this medicine.
• Careful consideration should be given to the use of Pentazocine during pregnancy particularly
during the first trimester (first 3 months) or at full term (end of pregnancy).
• Regular use during pregnancy may cause withdrawal symptoms in the newborn.
• Clinical monitoring of the newborn, particularly premature infants, is necessary if Pentazocine has
been used during labour.
• Pentazocine is passed into breast milk, but in very small amounts. It is advisable to avoid taking
Pentazocine whilst breastfeeding.
Driving and using machines
Pentazocine may cause sedation, dizziness and occasionally euphoria. If affected do not drive or use
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 drive.
• However, you would not be committing an offence if:
o The medicine has been prescribed to treat a medical or dental problem and
o You have taken it according to the instructions given by the prescriber or in the information
provided with the medicine and
o 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
Pentazocine contains lactose
If you have been told by your doctor that you have an intolerance to some sugars, contact your doctor
before taking this medicine.
3. How to take Pentazocine

Always take Pentazocine exactly as your doctor has told you. Check with your doctor or
pharmacist if you are not sure.

These capsules are to be taken orally.
These capsules should be taken after meals.

The usual starting dose is 1 to 2 capsules every three to four hours.
Your doctor may give you a lower dose if you are elderly.
Patients with liver or kidney problems
If you have liver or kidney problems, your doctor may reduce your dose.
Use in children
• Children over 12 years of age: 1 to 2 capsules every three to four hours.
• Children under 12 years of age: Not recommended.
If you take more Pentazocine than you should
If you accidentally take too many capsules, contact your doctor or nearest hospital emergency
department immediately for advice. Remember to take this leaflet or any remaining capsules with
Symptoms of overdose include: sleepiness or drowsiness (somnolence), slower or weaker
breathing (respiratory depression), low/high blood pressure (hypotension/hypertension), faster
heartbeat (tachycardia), seeing or hearing things that are not real (hallucinations), or fits (seizures,
convulsions). Poor circulation and unconsciousness or coma may occur in more severe cases.
If you forget to take your Pentazocine
Take it as soon as you remember, unless it is nearly time for your next dose. If you miss a dose, do
not take a double dose to make up for a forgotten dose.
If you stop taking Pentazocine
• It is important that you keep taking Pentazocine for as long as your doctor has told you to.
• If you stop taking the capsules you may develop the following withdrawal symptoms; mild
stomach cramps, feeling (nausea) or being sick (vomiting), nervousness or restlessness,
dizziness, fever and chills.
• Long-term use of Pentazocine, particularly in high doses, can lead to dependence.
If you have any further questions on the use of this medicine, ask your doctor or pharmacist.
4. Possible side effects
Like all medicines, Pentazocine can cause side effects although not everybody gets them.
Seek medical advice immediately if you develop the following symptoms:
• Allergic reactions: swelling of the face, throat or tongue, difficulty breathing or dizziness
• Frequent wheezing, breathlessness, abdominal pain, diarrhoea, fever, cough and rashes due to
an increase in certain white blood cells (eosinophillia)
• Severe blistering of the skin, mouth, eyes and genitals (toxic epidermal necrolysis)
Side effects (most frequent)
• Feeling sick (nausea) or being sick (vomiting)
• Feeling tired or drowsy
• Light-headedness
• Dizziness
• Sweating
Other side effects (frequency not known)
• High (hypertension) or low blood pressure (hypotension)

Slow (bradycardia) or fast heartbeat (tachycardia)
Feeling your heartbeat (palpitations)
Poor circulation
Seeing or hearing things that are not real (hallucinations). May occur occasionally
Feeling depressed or discontented (dysphoria)
Visual disturbances
Feeling disorientated
Mood changes
Difficulty sleeping (insomnia)
Tingling or numbness in the hands or feet (paraesthesia)
Fainting (syncope)
Intense feeling of well-being or elation (euphoria)
Fits (seizures)
Increased pressure in the skull
Thought disturbances
Reddening of the face (flushing)
Skin rashes
Skin rashes with the formation of wheals (urticaria)
Skin rash or inflammation (dermatitis)
Severe itching (pruritus)
Dry mouth
Pain in lower back or stomach (may be caused by a spasm of the ureter or bile duct)
Depression of the white blood cell count, which is usually reversible
Extremely small pupils of the eyes (miosis)
Breathing more slowly or weakly than usual (respiratory depression)
Muscle tremor
Low body temperature (hypothermia)
Difficulty passing urine
Changes in the rate or strength of uterine contractions during labour
Lack of sexual desire (decreased libido)

Reporting of side effects
If you get any side effects, talk to your doctor or pharmacist. 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.
5. How to store Pentazocine
• Keep this medicine out of the sight and reach of children.
• Do not use Pentazocine after the expiry date which is stated on the container after EXP. The
expiry date refers to the last day of that month.
• Store in a cool dry place.
• Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist
how to throw away medicines you no longer use. These measures will help to protect the
6. Contents of the pack and other information
What Pentazocine contains:
Each 50mg capsule contains Pentazocine Hydrochloride 50mg.
The other ingredients are: lactose, talc and magnesium stearate. The capsule shell contains black
iron oxide (E172), titanium dioxide (E171), erythrosine (E127), quinoline yellow (E104) and gelatin.

What Pentazocine looks like and contents of the pack:
Pentazocine are grey/light orange size 4 capsules, printed PZN 50.
Pentazocine is available in:
Pentazocine Capsules are available in packs of 100, 250 or 500 capsules.
Not all pack sizes may be marketed.
Product Licence Number:
Pentazocine 50mg Capsules: PL 11311/0530
Marketing Authorisation Holder and Manufacturer:
Tillomed Laboratories Ltd
220 Butterfield
Great Marlings
This leaflet was last revised in September 2017

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Further information

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