Domperidone

BRAND NAMES:

Motilium – It is available in two forms oral suspensions and oral tablets. 

Oral suspension- It contains the active ingredients of domperidone. It is available as an oral suspension used to treat nausea and vomiting.

Oral tablets- It contains the active ingredients of domperidone. It is available as an oral tablets for treating nausea and vomiting.

Nauzelin – It contains the active ingredients of domperidone. It is available in the form of oral tablets. It is used to treat the gastrointestinal symptoms.

Domstal- It contains the active ingredients of domperidone. It is available as baby syrup and oral tablets to treat nausea and vomiting.

Moperidona – It contains the active ingredients of domperidone. It is available in the form of a solution.

Vometa – It contains the active ingredients of domperidone. It is available as an oral suspension used to treat gastrointestinal symptoms.

Zilium– It contains the active ingredients of domperidone. It is available as a tablet used to treat nausea and vomiting.

MECHANISM OF ACTION:

Domperidone improves gastric emptying and shortens bowel transit time by enhancing esophageal and gastric peristalsis and decreasing esophageal sphincter pressure. Domperidone's antiemetic actions are due to its ability to inhibit dopamine receptors at both the chemoreceptor trigger zone and the stomach level. It has a high affinity for the D2 and D3 dopamine receptors, which are present in the chemoreceptor trigger zone just outside the blood-brain barrier and govern nausea and vomiting. It improves stomach emptying and shortens bowel transit time by enhancing esophageal and gastric peristalsis and decreasing esophageal sphincter pressure.

PHARMACOKINETICS:

Absorption: Domperidone is quickly absorbed from the gastrointestinal tract. Peak plasma concentration occurs within 2 hours after taking a dose.

Distribution: Domperidone is 91-93% bound to plasma proteins. Distribution studies with radiolabelled drugs in animals have shown wide tissue distribution, but low brain concentration.

Metabolism: Domperidone is substantially metabolized in the liver and gut after oral treatment. This happens by hydroxylation and N-dealkylation. Domperidone is almost primarily metabolized by CYP3A4/5, with modest contributions from CYP1A2, CYP2D6, and CYP2C8 identified.

Excretion: Domperidone is eliminated 31% in urine and 66% in feces.

PHARMACODYNAMICS:

Domperidone is a dopamine receptor-specific blocker. It accelerates gastrointestinal peristalsis, stimulates prolactin secretion, and acts as an antiemetic.

DOSAGE AND ADMINISTRATION:

Tablet - Take one 10 mg tablet up to three times once a day, preferably before meals. It is typically not suggested to take more than three pills each day, however, in exceptional situations, your doctor may prescribe up to four tablets. 

Oral suspensions: The normal dose is 10 ml given up to three times per day, preferably before meals. Avoid taking more than 30ml per day. 

Suppositories: The normal dose is one 30 mg suppository twice a day. Do not use more than two suppositories in one day.

Domperidone can be used up to three times per day, but only as needed. Leave at least 8 hours between each dosage. Domperidone is best taken before a meal. Take it 15-30 minutes before your meal.

DRUG INTERACTIONS:

Drug interactions may include

• Fungal infections-  ketoconazole, fluconazole or voriconazole.
• Bacterial infections- Erythromycin, clarithromycin, telithromycin, moxifloxacin, pentamidine.
• Heart problems – amiodarone, dronedarone, quinidine, disopyramide, dofetilide, sotalol, diltiazem
• Psychoses- haloperidol, primozide, sertindole.
• Depression – citalopram, escitaloprm
• Gastrointestinal disorders- cisapride, dolasetron, prucalopride
• Allergy- mequitazine, mizolastine
• Malaria- halofantrine
• AIDS/HIV- protease inhibitor
• Cancer – toremifene, vandetanib

CONTRAINDICATIONS:

Patients with moderate to severe liver impairment. In patients with established cardiac conduction interval prolongation, especially QTc patients with substantial electrolyte imbalance or underlying cardiac illnesses such as congestive heart failure. Co-administration of QT-prolonging medicines with strong CYP3A4 inhibitors.

SIDE EFFECTS:

Side effects of domperidone may include

• Dry mouth
• Headache
• Swelling of the breast in men
• Hives
• Hot flashes
• Itchy skin
• Eye itchiness, pain swelling, or redness
• Breast pain
• Menstrual irregularities
• Swelling of the mouth
• Loss of muscle control or balance
• Swelling of hands, face, lower legs or feet
• Fast, pounding, irregular, or racing heartbeat.
• OVERDOSE:
• Although there is no particular antidote for domperidone, in the event of an overdose, normal symptomatic therapy should be administered immediately.
• Difficulty in speaking
• Disorientation
• Dizziness
• Fainting
• Irregular heartbeat
• Light-headedness
• Loss of balance or muscle control

TOXICITY:

Overdose of domperidone leads to toxicity.  Standard symptomatic treatment should be given immediately.

STORAGE:

Store at room temperature between 68°-77° F (20°-25°C) as advised.

Protect against light.

Do not store domperidone suppositories in the refrigerator or freezer. Do not store over 77° F. (25°C).