Drug Interactions between Doc-Q-Lax and dofetilide

GENERALLY AVOID: Chronic use of stimulant laxatives may decrease the absorption of fat-soluble vitamins (A, D, E, and K) and minerals such as calcium, potentially leading to deficiencies. This effect is due to accelerated intestinal transit time, which reduces nutrient absorption.

MANAGEMENT: To minimize this risk, limit the use of stimulant laxatives to short-term or occasional use.

In vitro data suggest that grapefruit juice may inhibit the CYP450 3A4 first-pass metabolism of dofetilide. Decreased first-pass metabolism may increase dofetilide concentrations and increase the risk of QT interval prolongation and arrhythmias. The clinical significance is unknown, since dofetilide has a high oral bioavailability and a low affinity for CYP450 3A4. The manufacturer recommends caution.

The use of stimulant laxatives is contraindicated in patients with or who may have acute surgical abdomen or appendicitis. These patients may be candidates for emergency surgery. Stimulant laxatives should also not be administered to patients with abdominal pain, particularly if the cause has not been determined.

The use of stimulant laxatives is contraindicated in patients with anal or rectal fissures. These preparations may cause irritation, burning sensation, and proctitis.

The use of laxatives is contraindicated in patients with intestinal obstruction disorders. Patients with intestinal obstruction disorders may need their underlying condition treated to correct the constipation. Some laxatives require reduction in the colon to their active form to be effective which may be a problem in patients with intestinal obstruction.

The use of laxatives is contraindicated in patients with intestinal obstruction disorders. Patients with intestinal obstruction disorders may need their underlying condition treated to correct the constipation. Some laxatives require reduction in the colon to their active form to be effective which may be a problem in patients with intestinal obstruction.

The use of laxatives is contraindicated in patients with inflammatory bowel disease. Patients with inflammatory bowel disease may experience colonic perforation with use of stimulant laxatives.

The use of laxatives is contraindicated in patients with inflammatory bowel disease. Patients with inflammatory bowel disease may experience colonic perforation with use of stimulant laxatives.

Dofetilide is contraindicated in patients with congenital or acquired long QT syndromes. Dofetilide should not be used in patients with a baseline QT interval of QTc >440 msec (500 msec in patients with ventricular conduction abnormalities).

Dofetilide is contraindicated in patients with severe renal impairment (calculated creatinine clearance <20 mL/min). The risk of QT interval prolongation, Torsade de Pointes, and ventricular arrhythmias is directly related to dofetilide plasma concentration. A reduced creatinine clearance will increase dofetilide plasma concentration. In patients with mild and moderate renal impairment, the risk of arrhythmias can be reduced by controlling the plasma concentration through adjustment of the initial dofetilide dose according to creatinine clearance. Patients undergoing dialysis were not included in clinical studies, and appropriate dosing recommendations for these patients are unknown. There is no information about the effectiveness of hemodialysis in removing dofetilide from plasma.

Dofetilide should be avoided in patients that experience symptoms that may be associated with altered electrolyte balance, such as excessive or prolonged diarrhea, sweating, or vomiting or loss of appetite or thirst, these conditions should immediately be reported to their health care provider.

Dofetilide should be avoided in patients that experience symptoms that may be associated with altered electrolyte balance, such as excessive or prolonged diarrhea, sweating, or vomiting or loss of appetite or thirst, these conditions should immediately be reported to their health care provider.

Dofetilide should be avoided in patients that experience symptoms that may be associated with altered electrolyte balance, such as excessive or prolonged diarrhea, sweating, or vomiting or loss of appetite or thirst, these conditions should immediately be reported to their health care provider.

Serum potassium should be maintained within the normal range before dofetilide treatment is initiated and should be maintained within the normal range while the patient remains on dofetilide therapy. In clinical trials, potassium levels were generally maintained above 3.6 to 4.0 mEq/L. Exercise care when using this agent in patients with hypokalemia.

Dofetilide has not been studied in patients with severe hepatic impairment. Dofetilide should be used with particular caution in these patients.

Dofetilide should be avoided in patients that experience symptoms that may be associated with altered electrolyte balance, such as excessive or prolonged diarrhea, sweating, or vomiting or loss of appetite or thirst, these conditions should immediately be reported to their health care provider.