phenytoin, Dilantin, Dilantin-125 (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

Drugs that may decrease phenytoin levels and reduce effectiveness include carbamazepine, chronic alcohol abuse, reserpine, and sucralfate (Carafate).

The oral absorption of phenytoin can be reduced by any of the following:

  • antacids containing magnesium,
  • calcium carbonate, or aluminum;
  • calcium salts; or enteral feeding products (tube feedings).

Separating the administration of phenytoin and enteral feeding products, antacids, or calcium salts by at least 2 hours will help avoid this interaction.

PREGNANCY: There is an increased risk of malformations and birth defects in women taking phenytoin. Thus, phenytoin should be used in pregnancy only if the physician feels that the potential benefit outweighs the risk.

NURSING MOTHERS: Phenytoin is secreted into breast milk. Breast feeding is not recommended for persons taking phenytoin.

SIDE EFFECTS: Many adverse effects can occur during phenytoin therapy including dizziness, drowsiness, difficulty focusing (vision), unsteady gate, tiredness, abnormal involuntary movements, nausea, vomiting, constipation, abdominal pain, and loss of appetite.

Children and young adults can develop overgrowth of the gums during long-term therapy which requires regular treatment by a dentist. Good oral hygiene and gum massage may reduce the risk. R

ashes can occur in between 1 in 20 and 1 in 10 persons; some may be severe. Additionally, darkening coloration of the skin may develop (more commonly in women). Phenytoin can produce unusual growth of hair in some patients. This reaction most commonly affects the arms and legs but can also affect the trunk and face; it may be irreversible.



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