Tramadol (Zamadol)

How does it work?

Zamadol capsules, Zamadol melt tablets and Zamadol injection all contain the active ingredient tramadol hydrochloride, which is a type of medicine called an opioid painkiller. (NB. Tramadol is also available without a brand name, ie as the generic medicine.)

Opioid painkillers work by mimicking the action of naturally occurring pain-reducing chemicals called endorphins. Endorphins are found in the brain and spinal cord and reduce pain by combining with opioid receptors.

Tramadol mimicks the action of our natural endorphins by combining with the opioid receptors in the brain and spinal cord. This blocks the transmission of pain signals sent by the nerves to the brain. Therefore, even though the cause of the pain may remain, less pain is actually felt.

Tramadol also works by enhancing the activity of neurotransmitters in the brain and spinal cord. Neurotransmitters are chemical compounds that act as chemical messengers between the nerve cells. Tramadol enhances the effect of the neurotransmitters serotonin and noradrenaline, and this action also helps relieve pain.

Tramadol is a fairly strong painkiller that is used in the management of moderate to severe pain. It is given by injection when administration by mouth is not possible, for example for pain following surgery. The injection is given into a muscle or vein, or via a drip into a vein (intravenous infusion).

Zamadol capsules and melt tablets are taken by mouth up to six times a day, depending on the severity of the pain. Zamadol melt tablets are designed to dissolve in the mouth without water and be swallowed with the saliva. Alternatively they can be dissolved in half a glass of water before taking. These forms of tramadol should not be taken more often than every four hours and you should not exceed the dose prescribed by your doctor.

For more prolonged pain relief, modified release forms of tramadol that can be taken once or twice a day are available. See the products linked at the end of this factsheet for more information.

What is it used for?

  • Moderate to severe pain.


  • This medicine may cause drowsiness. If affected do not drive or operate machinery. Alcohol should be avoided.
  • Some people may rarely experience withdrawal symptoms when they stop taking this medicine. These may include feeling agitated, anxious, nervous or shaky, or having difficulty sleeping. Tell your doctor if you experience any of these symptoms after stopping this medicine. These effects usually disappear after a few days.
  • This medicine is not recommended for children under 12 years of age.
  • This medicine is not recommended for people with severely decreased kidney function.
  • Zamadol melt tablets contain aspartame and so may not be suitable for people with an inherited disorder of protein metabolism called phenylketonuria.

Use with caution in

  • Elderly people
  • Decreased kidney function
  • Decreased liver function
  • Asthma
  • Slow, shallow breathing (respiratory depression)
  • History of drug dependence or abuse
  • Head injury
  • Increased pressure in the brain (raised intracranial pressure)
  • Reduced blood flow to vital internal organs (shock)
  • History of convulsions, eg epilepsy.

Not to be used in

  • People under the influence of (intoxicated with) alcohol, sleeping tablets, tranquilizers, psychotropic drugs (those affecting mood or emotions) or other painkillers that act on the brain, eg morphine, codeine
  • People who have taken a monoamine-oxidase inhibitor antidepressant (MAOI) in the last 14 days
  • Pregnancy
  • Breastfeeding
  • Uncontrolled epilepsy.

This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.

Pregnancy and Breastfeeding

Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.

  • The safety of this medicine during pregnancy has not been established. It may be harmful to a developing baby and could cause withdrawal symptoms in a newborn baby if used during the third trimester. The manufacturer therefore states that this medicine should not be used during pregnancy. Seek medical advice from your doctor.
  • This medicine passes into breast milk in small amounts. The manufacturer recommends that women who are breastfeeding should not use this medicine. Seek medical advice from your doctor.

Label warnings

  • This medication may cause drowsiness. If affected do not drive or operate machinery. Avoid alcoholic drink.

Side effects

Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.

  • Disturbances of the gut such as diarrhoea, constipation, nausea, vomiting or abdominal pain
  • Dizziness
  • Drowsiness
  • Headache
  • Sweating
  • Awareness of your heartbeat (palpitations)
  • Increased heart rate (tachycardia)
  • A drop in blood pressure that occurs when going from lying down to sitting or standing, which results in dizziness and lightheadedness (postural hypotension)
  • Skin reactions such as rash and itch
  • Blurred vision
  • Dry mouth
  • False perceptions of things that are not really there (hallucinations)
  • Nightmares
  • Confusion
  • Changes in mood
  • Slow, shallow breathing (respiratory depression)
  • Muscle weakness
  • Difficulty passing urine

The side effects listed above may not include all of the side effects reported by the drug's manufacturer.For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.

How can this medicine affect other medicines?

It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while taking this one, to ensure that the combination is safe.

The manufacturer states that this medicine should not be taken at the same time as, or within two weeks of, MAOI antidepressants such as phenelzine or tranylcypromine.

There may be an increased risk of convulsions or seizures if tramadol is taken with the following medicines:

  • antipsychotic medicines
  • bupropion
  • mefloquine
  • SSRI antidepressants (eg fluoxetine)
  • tricyclic antidepressants (eg amitriptyline).

If tramadol is taken with SSRI antidepressants such as fluoxetine, or triptans for migraine such as sumatriptan, there may also be an increased risk of other side effects, as all these medicines enhance the activity of serotonin in the brain.

There may be an increased risk of drowsiness and sedation if tramadol is taken with any of the following (which can also cause drowsiness):

  • alcohol
  • antipsychotics, eg haloperidol
  • barbiturates, eg phenobarbital, amobarbital
  • benzodiazepines, eg diazepam, temazepam
  • other opioids, eg morphine, codeine
  • sedating antihistamines, eg chlorphenamine, hydroxyzine
  • sleeping tablets, eg zopiclone
  • tricyclic antidepressants, eg amitriptyline.

Carbamazepine may decrease the blood level of tramadol, which may make it less effective at relieving pain.

Tramadol may enhance the anti-blood-clotting effect of anticoagulant medicines such as warfarin. If you are taking warfarin your blood clotting time (INR) should be monitored when you start and stop treatment with tramadol.

Other medicines containing the same active ingredient

Dromadol SR Larapam SR Mabron
Tramake Tramake Insts Zamadol SR
Zamadol 24hr Zydol Zydol SR
Zydol XL

Tramadol capsules and injection are also available without a brand name, ie as the generic medicine.