Maxolon tablets contain the active ingredient metoclopramide hydrochloride, which is a type of medicine called a dopamine antagonist. (NB. Metoclopramide is also available without a brand name, ie as the generic medicine.) Metoclopramide is an antisickness medicine, though it also has other uses due to its action on the gut.
Metoclopramide works primarily by blocking dopamine receptors found in an area of the brain known as the chemoreceptor trigger zone (CTZ). The CTZ is activated by nerve messages from the stomach when an irritant is present. It is also activated directly by agents circulating in the blood, for example anti-cancer medicines. Once activated, it sends messages to another area of the brain, the vomiting centre, which in turn sends messages to the gut, causing the vomiting reflex.
Blocking the dopamine receptors in the CTZ prevents nausea messages from being sent to the vomiting centre. This reduces the sensation of sickness and prevents vomiting.
Metoclopramide also acts in the upper end of the digestive system, where it enhances the action of a natural chemical called acetylcholine. Increasing the action of acetylcholine results in the tightening of the muscles at the entry to the stomach, relaxation of the muscles at the exit of the stomach and increased contraction of the muscles in the stomach itself. These actions speed the passage of food through the stomach into the intestine, which physically helps to prevent vomiting.
Both actions make metoclopramide useful in treating nausea and vomiting due to many causes, including anti-cancer chemotherapy and radiotherapy, various digestive disorders, heart failure, following surgery and anaesthetics, and in migraine.
Due to its action on the gut, metoclopramide also has several other uses. It is useful in migraine, not only for relieving nausea, but also because during a migraine attack stomach emptying is slowed, which can prevent painkillers from being absorbed. Metoclopramide speeds up the passage of painkillers from the stomach to the intestine, from where they are absorbed to relieve the headache.
Metoclopramide is often given before investigative procedures in hospital for its action on the gut, for example it helps to speed the passage of a barium meal through the gut.
Metoclopramide can also be used to restore normal muscle tone and function to the gut following surgery and in various digestive disorders. This helps relieve symptoms such as indigestion, pain, bile regurgitation, flatulence, acid reflux and heartburn.
In adults over 20 years of age metoclopramide is used for the following conditions:
Use in patients under 20 years of age is not recommended and is restricted to the following conditions:
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.
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.
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. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
The side effects listed above may not include all of the side effects reported by the medicine'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.
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 make sure that the combination is safe.
Due to its action on the gut, metoclopramide may affect the absorption of various other medicines that are taken by mouth. A positive application of this is for relieving migraine, where metoclopramide speeds the absorption into the bloodstream of painkillers such as paracetamol and aspirin.
Metoclopramide may decrease the blood level of atovaquone.
Metoclopramide may increase the blood level of ciclosporin.
Metoclopramide may increase the drowsiness and sedation that are side effects of opioid painkillers such as morphine.
Metoclopramide may oppose the effect of medicines for Parkinson's disease that work by stimulating dopamine receptors in the brain, for example ropinirole, pergolide, rotigotine, bromocriptine.
Metoclopramide may oppose the prolactin lowering effect of bromocriptine or cabergoline.
There may be an increased risk of side effects known as extrapyramidal effects if metoclopramide is taken with tetrabenazine or with antipsychotic medicines, eg chlorpromazine. Extrapyramidal side effects involve abnormal movements of the hands, legs, face and tongue, for example tremor or twitching.
There may be an increased risk of a side effect called the serotonin syndrome if metoclopramide is taken in combination with the following medicines:
The following medicines may oppose the effect of metoclopramide on the gut:
Metoclopramide tablets, oral solution and injection are also available without a brand name, ie as the generic medicine.