Domperidone is used in the treatment of nausea and vomiting arising due to a myriad of reasons. It is also a prokinetic agent and in increases the gastric motility while reducing the gastric emptying time. This effect of Domperidone is used in the treatment of gastroparesis. Its primary action is as an anti-dopaminergic agent, and exerts this effect on the vomiting centre in the brain. However it does not cross the blood-brain barrier and is thus devoid of the extra-pyramidal side effects that may be seen with other drugs like metoclopramide. This also enables the use of Domperidone for the treatment of nausea and vomiting in patients suffering from Parkinson’s disease or Parkinsonism.
How Domperidone Works: Domperidone is an anti-dopaminergic drug which forms the basis of its anti-emetic effects. It has a higher affinity for D2 and D3 type of dopamine receptors. Domperidone acts on the vomiting centre in the brain or the chemoreceptor trigger zone (CTZ) in the area postrema of the fourth ventricle at the medulla oblongata. This centre falls outside the blood-brain barrier thus allowing the action of Domperidone without penetration of this barrier. Domperidone also increases gastric motility and reduces gastric emptying time. It increases the duration and frequency of gastric antral and duodenal contractions, thus allowing the gastric contents to be emptied quicker.
How To Take Domperidone: Domperidone is a commonly used anti-emetic agent and is effective in various causes of nausea and vomiting such as drug induced, post-operative, chemotherapy associated (less effective), radiation induced and migraine associated. As a prokinetic agent, it is used in conditions with gastric dysmotility such as that seen in diabetics and as a pre-anaesthetic drug. Domperidone is used as adjuvant treatment for dyspepsia and gastro-esophageal reflux disease (GERD) along with antacids and proton-pump inhibitors. It greatly reduces the sensations of fullness, sickness and bloating and prevents episodes of regurgitation. Since Domperidone crosses the blood-brain barrier poorly, it can be used in Parkinsonism to treat dose-limiting side effects of levodopa of nausea and vomiting. Another use of Domperidone has been in the promotion of lactation due to its prolactin inhibiting property. However, Domperidone has not been approved for this use yet. Domperidone is available as oral tablets in the strength of 10 mg. It is also available as rectal suppositories in the strengths of 10 mg, 30 mg and 60 mg. Use as a suppository is indicated either when the patient is not able or permitted to take anything per orally, or in conditions of severe vomiting where the medication cannot be retained when taken orally. Domperidone is also available as a syrup suspension and as drops for administration in children. The recommended dosage for use in nausea and vomiting is 10 mg at a time. If required, Domperidone may be taken up to 4 times a day with a maximum permissible dose of 40 mg/ day. For children, the dose of Domperidone is 0.3-0.6 mg/kg.
Precautions And Side Effects Of Domperidone : Domperidone is not to be used in patients with prolactinoma, intestinal perforation, intestinal obstruction, gastro-intestinal bleeding, hepatic dysfunction and in very young children with body weight less than 35 kg. Domperidone can cause QT interval prolongation and should not be used with other drugs with this effect such as ketoconazole, cimetidine, erythromycin and terbinafine. It should be used with caution in children and patients with heart disease or electrolyte imbalances. Domperidone can cause galactorrhoea (abnormal milk production) and gynaecomastia (enlargement of breast tissue in males). Other side effects seen with the use of Domperidone are stomach cramps and pain, decreased libido, nervousness, agitation, blurred vision and allergic skin rashes.