General

**Off Market Drug**
This medication is no longer available in the United States. Information provided here is for reference purposes only.

Pronunciation:
ten-a-pa-nor

Trade Name(s)

• Ibsrela

Ther. Class.

anti irritable bowel syndrome agents

Pharm. Class.

sodium hydrogen exchanger 3 inhibitors

Indications

Irritable bowel syndrome with constipation (IBS-C).

Action

Inhibits the sodium/hydrogen exchanger 3 which results in a reduction in sodium reabsorption from the small intestine and colon and an increase in water secretion into the intestinal lumen. The increased water secretion accelerates intestinal transit time and softens stool consistency.

Therapeutic Effect(s):

Increased frequency of bowel movements with decreased pain associated with IBS-C.

Pharmacokinetics

Absorption: Minimally absorbed, action is primarily local.

Distribution: Stays within the GI tract with minimal distribution.

Protein Binding: 99%.

Metabolism and Excretion: Primarily metabolized in liver via CYP3A4 and CYP3A5 isoenzymes. Primarily excreted in feces as unchanged drug; minimal excretion in urine.

Half-life: Unknown.

TIME/ACTION PROFILE (improvement in IBS-C symptoms)

Contraindication/Precautions

Contraindicated in:

• Known/suspected mechanical GI obstruction
• Pedi:   Children <12 yr (↑ risk of severe dehydration in children <6 yr).

Use Cautiously in:

• OB:   Use only if potential maternal benefit justifies potential fetal risk (minimal fetal exposure expected); .
•  Lactation: Use while breastfeeding only if potential maternal benefit justifies potential risk to infant
• Pedi:  Children 12–18 yr (safety and effectiveness not established).

Adverse Reactions/Side Effects

CNS: dizziness

GU: diarrhea, abdominal distension, flatulence

* CAPITALS indicate life-threatening.
Underline indicate most frequent.

Interactions

Drug-Drug

None reported.

Route/Dosage

PO (Adults): 50 mg twice daily.

Availability

Tablets: 50 mg

Assessment

• Assess for abdominal distension, presence of bowel sounds, and usual pattern of bowel function.
• Assess color, consistency, and amount of stool produced.

Implementation

• PO Administer immediately prior to breakfast or the first meal of the day and immediately prior to dinner.

Patient/Family Teaching

• Instruct patient to take tenapanor as directed. If a dose is missed, omit and take next dose at regular time. Do not take 2 doses at same time.
• Advise patient to notify health care professional if severe diarrhea occurs.
• Advise patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and consult health care professional before taking any new medications.
• Instruct patient to store at room temperature in the original container and protect from moisture. Do not put in another container (repackage). Do not remove the desiccant from the bottle.
• Advise females of reproductive potential to notify health care professional if pregnancy is planned or suspected or if breastfeeding. Maternal use is not expected to result in fetal exposure due to minimal systemic absorption.

Evaluation/Desired Outcomes

Increased frequency of bowel movements with decreased pain associated with IBS-C.