Effect of Antacids on Phenytoin Bioavailability

  title={Effect of Antacids on Phenytoin Bioavailability},
  author={B. Carter and W. Garnett and J. Pellock and M. Stratton and J. R. Howell},
  journal={Therapeutic Drug Monitoring},
Eight subjects were studied in a randomized crossover design to determine the effect of aluminum-magnesium hydroxide (AMH), calcium carbonate (CC), and aluminum hydroxide-magnesium trisilicate (AHMT) on the bioavailability of a single, 600-mg dose of phenytoin administered orally. Each subject received phenytoin alone on two separate occasions and phenytoin plus each of the three antacids on three other occasions. Each antacid was administered as 160 mEq at 1 and 3 hr after each meal and at… Expand
Effect of Two Administration Schedules of an Enteral Nutrient Formula on Phenytoin Bioavailability
Factors other than direct contact may be responsible for the observed decreases in PHT concentrations by coadministered ENFs, and the bioavailability of PHT was not decreased by either ENF administration schedule. Expand
Comparative effects of an elemental and a complex enteral feeding formulation on the absorption of phenytoin suspension.
The data suggest that the two enteral feeding formulations investigated do not interfere with nor enhance or accelerate phenytoin absorption as determined by a single-dose study. Expand
Influence of Enteral Feedings on Phenytoin Sodium Absorption from Capsules
It is suggested that enteral feedings do not affect the serum concentrations of phenytoin after a single dose given in capsule form. Expand
Effect of food on absorption of Dilantin Kapseals and Mylan extended phenytoin sodium capsules
Results suggest that when taking phenytoin sodium with food, product switches may result in either side effects or loss of seizure control. Expand
Drug-Antacid Interactions: Assessment of Clinical Importance
The majority of literature reports on interactions with antacids have been overemphasized; only ferrous sulfate-, isoniazid-, and tetracycline-antacid interactions fall into a category I importance (scale I–III of descending importance). Expand
Clinically Significant Drug Interactions with Antacids
The recent trend of developing OTC drugs as combination formulations of an antacid and an H2RA is a concern because these drugs will increase the risk of DDIs by dual mechanisms, i.e. a gastric pH-dependent mechanism by H2RAs and a cation-mediated chelation mechanism by antacids. Expand
Interaction of oral phenytoin with enteral feedings.
A 48-yr-old man with squamous cell carcinoma of the lung, hypercalcemia, and brain metastases with seizures was treated with phenytoin and a lower dose of pheny toin administered between feedings was placed on bolus nasogastric feedings. Expand
Interactions Between Anticonvulsants and Other Commonly Prescribed Drugs
Probably the most predictable interaction that necessitates dosage adjustment is accumulation of PB caused by VPA, and intentional inhibition of PRM metabolism by nicotinamide serves as an example of attempts to utilize an interaction for improved therapeutic effect. Expand
Phenytoin kinetics during pregnancy and the puerperium
During pregnancy changes in maternal physiology and plasma composition may alter drug binding and dose requirements, and it is appropriate to monitor saliva phenytoin concentrations regularly both during pregnancy and the puerperium. Expand
Treatment of Concomitant Illneses in Patients Receiving Anticonvulsants
As epilepsy often is a chronic condition requiring prolonged therapy with anticonvulsants, patients being treated for epilepsy can be at risk when they are prescribed other drugs for concomitant diseases, and drugs that are not metabolised and are not highly protein bound, such as gabapentin, lamotrigine and vigabatrin, have a clear advantage in terms of a lower interaction potential. Expand