Pantoprazole exerts its full effect in a strongly acidic environment (pH<3) and remains mostly inactive at higher pH valuse, which explains its selectivity for the acid secreting parietal cells of the stomach. Therefore, the complete pharmacological and therapeutic effect for Pantoprazole can only be achieved in the acid-secreting parietal cells. By means of a feedback mechanism this effect is diminished at the same rate as acid secretion is inhibited.

 

Domperidone

Domperidon is a dopamine antagonist with antiemetic properties. Domperidone does not readily cross the blood-brain barrier. It seldom causes extrapyramidal side effects, but does cause a rise in prolactin levels. Its antiemetic effect may be due to a combination of peripheral (gastrokinetic) effects and antagonism of central dopamine receptors in the chemoreceptor trigger zone which lies in the area postrema and is regarded as being outside the blood-brain barrier.

 

It also antagonises the behavioural effects of dopamine much more effectively when administered intracerebrally than when given systemically. These findings, together with the low concentrations found in the brain, indicate a predominantly peripheral effect of domperidone on dopamine receptors.

 

Studies in humans have shown intravenous and oral domperidone to increase lower oesophageal pressure, improve antroduodenal motility and accelerate gastric emptying. Domperidone has no effect on gastric secretion.

Severely impaired liver function.

 

• Known hypersensitivity to domperidone or any of the excipients
• Prolactin-releasing pituitary tumour (prolactinoma)
• Co-administration with oral ketoconazole (see Interactions)

 

DOMPERIDONE should not be used whenever stimulation of gastrointestinal motility might be dangerous such as in the presence of gastrointestinal haemorrhage, mechanical obstruction, or perforation.

There have been reports of allergic reactions such as skin rash, pruritus and in isolated cases also urticaria, angioedema or anaphylactic shock.

There have been less frequent reports of nausea, dizziness or disturbances in vision (blurred vision).

Peripheral edema, depression, fever or myalgia have been reported in individual cases.

Pantoprazole is not indicated for mild gastro-intestinal complaints such as nervous dyspepsia.

 

Prior to treatment, the possibility of a malignant gastric ulcer or a malignant disease of the oesophagus should be excluded, as the treatment with Pantoprazole may alleviate the Diagnosis of reflux oesophagitis should be confirmed by endoscopy.

 

Immune system:   Very rare: allergic reaction

 

Endocrine:    Rare: increased prolactin levels

 

Nevous system:  Very rare: extrapyramidal side effects

 

Gastrointestinal:  Rare: gastrointestinal disorders, including very rate transient intestinal cramps

 

Skin and subcutaneous tissue: Very rare: urticaria

 

Reproductive system:  Rare: amenorrhoea

 

Other:  Rare: galactorrhoea, gynaecomastia

 

As the hypophysis is outside the blood brain barrier, domperidone may cause an increase in prolactin levels. In rare cases this hyperprolactinaemia may lead to neuro-endocrinological side effects such as galactorrhoea, gynaecomastia and amenorrhoea.

 

Extrapyramidal phenomena are very rare in neonates and infants, and exceptional in adults. These side effects reverse spontaneouly and completely as soon as the treatment is stopped.