What Is Therapeutic Monitoring?
The therapeutic monitoring of domperidone should be achieved by using lowest effective dose over shortest duration essential for the management of vomiting and nausea. Normally, the 10mg tablets of domperidone are intended for oral administration. It is also suggested to take orally before the meals, since if it is taken after meals, there will be a slight delay in the absorption of drug. Moreover, strict adherence to the time is also recommended between the doses, in case of missing a dose, it should be retaken as soon as possible but the regime could not be doubled to compensate the missed dose. A determined duration of treatment should fall within one week.
Adults and adolescents
The normal dosage regime for therapeutic monitoring in the patients weighing equal or more than 35 kg, aging 12 years or above, it has been recommended as three times per day, considering the extensive dose of 30 mg per day. However, the children (aged less than 12 yrs.), infants, neonates, as well as adults with weight less than 35 kg are prohibited to use domperidone tablets due to the possibility of inaccurate dosing.
The domperidone is also known to increase the prolactin levels by increasing the concentration of prolactin in plasma. However, these increased levels only persist with chronic administration and returns to normal when the medication is discontinued. The plasma concentration level after the persistent two weeks of oral administration of 30 mg domperidone, when checked after 90 minutes of medicine administration represented plasma prolactin level significantly persistent at 25 ng/mL in males as compared to the normal that is 5 ng/mL. however, in females, it was found to be 117 ng/mL after the first dose, which later reduced up to 56 ng/mL after a total of 14 doses.
The dosing regimen of domperidone should be reduced in the patients with severe renal impairment since elimination half-life of domperidone is likely to be delayed in the cases of extensive renal impairment. Therefore, the frequency of administration of domperidone in renal impaired cases should be reduced by 1 to 2 times per day instead of thrice on the basis of severity of impairment. Such patients should be therapeutically monitored for any possible renal impairment.
Furthermore, the domperidone is also contraindicated in individuals with severe to moderate liver disorders. However, in the case of mild hepatic impairment, there is no need to adjust the dose. There is also some evidence that domperidone may be excreted through breast milk but the amount is negligible, that is approximately 0.1% of the parental weight-adjusted dosage. Since it is not evident whether it is harmful for the baby or not, it is therefore not recommended to breast feed the baby while taking domperidone. As far as the infants and children are concerned, the domperidone oral administration is prohibited in the individuals with less than 35 kg. Since the blood-brain barriers and metabolic functions in infants are not fully developed, there is a potential risk of developing neurological side effects in infants. Therefore, it is recommended to either prohibit the use of this drug or if essential, it should be given with accurate determined of the drug. This is because a slight overdose may induce extensive nervous system disorders.
It has also shown to affect the human performance and mental alertness by presenting somnolence and dizziness in the patient. Therefore, it is also restricted to use heavy machinery or drive after taking domperidone.
Overdosage Symptoms and signs
The over dosage is usually observed in children and infants, representing extrapyramidal reactions, somnolence, disorientation, convulsion, altered consciousness, agitation, etc. No specific antidote is known against domperidone; however, in the case of overdose, it is recommended to administer activated charcoal or perform gastric lavage within 1hour of ingestion. In addition, the anti-Parkinsonian or anti-cholinergic agents are also significant in the management of extrapyramidal reactions caused by the over dose of domperidone, whereas supportive therapy and Close observation is highly recommended in such cases.