Misoprostol

INTRODUCTION

Indications

Prevention of gastric mucosal injury from NSAIDs, including aspirin, in high-risk patients (geriatric patients, debilitated patients, or those with a history of ulcers). With mifepristone for termination of pregnancy. Unlabeled Use: Treatment of duodenal ulcers.

Action

Acts as a prostaglandin analogue, decreasing gastric acid secretion (antisecretory effect) and increasing the production of protective mucus (cytoprotective effect). Causes uterine contractions. Therapeutic Effects: Prevention of gastric ulceration from NSAIDs. With mifepristone terminates pregnancy of less than 49 days.

Adverse Reactions/Side Effects

CNS: headache. GI: abdominal pain, diarrhea, constipation, dyspepsia, flatulence, nausea, vomiting. GU: miscarriage, menstrual disorders.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Monitor improvements in GI symptoms (gastritis, heartburn, and so forth) to help document whether drug therapy is successful in preventing gastric damage or duodenal ulcers.

Interventions

• In cases of NSAID-induced gastritis, implement appropriate manual therapy techniques, physical agents, and therapeutic exercises to reduce musculoskeletal pain and decrease the need for aspirin and other NSAIDs.

Patient/Client-Related Instruction

• Advise patient to avoid alcohol and foods that may cause an increase in GI irritation.

• Inform patient that misoprostol will cause spontaneous abortion. Women of childbearing age must be informed of this effect through verbal and written information and must use contraception throughout drug treatment. If pregnancy is suspected, the woman should stop taking misoprostol and notify her health care professional immediately.

• If used with mifepristone to terminate pregnancy, inform patient that vaginal bleeding and uterine cramping will probably occur. Bleeding or spotting occurs for an average of 9–16 days, but may continue for more than 30 days. Instruct patient to report any severe or unusual cramping, bleeding, or pelvic pain that extends beyond the expected time periods.

• Instruct patient to report bothersome side effects, including severe or prolonged headache, menstrual irregularities, or GI problems (nausea, diarrhea, vomiting, constipation, heartburn, flatulence, abdominal pain).

Pharmacokinetics

Absorption: Well absorbed following oral administration and rapidly converted to its active form (misoprostol acid).

Distribution: Unknown.

Protein Binding: 85%.

Metabolism and Excretion: Undergoes some metabolism and is then excreted by the kidneys.

Half-life: 20–40 min.

Contraindications/Precautions

Contraindicated in: Hypersensitivity to prostaglandins; Pregnancy or lactation (when used to prevent NSAID-induced gastric injury).

Use Cautiously in: Patients with childbearing potential; Children ...