Starting IBSRELA With Enalapril?Arrange a Blood-Pressure Plan

If you take enalapril and are starting IBSRELA (tenapanor) for irritable bowel syndrome with constipation, tell both the dispensing pharmacist and the clinician managing your blood pressure. The U.S. IBSRELA label says to monitor blood pressure and increase enalapril if needed when the two are used together.¹ Any increase is a prescribing decision.

What the interaction study measured

The label reports a study in healthy people using a single 20 mg enalapril dose alongside tenapanor 30 mg twice daily at steady state. Enalapril’s total exposure fell 64% and that of its active metabolite, enalaprilat, fell 52%.¹

The tenapanor regimen was lower than the approved IBSRELA dose of 50 mg twice daily. These were measurements of medicine exposure, not percentages of patients whose blood pressure rose.¹ They cannot tell you to double a tablet or predict your individual response.

Tenapanor inhibits an intestinal uptake transporter called OATP2B1, which is involved in enalapril absorption.¹ Ask the pharmacist to review your complete medicine list; do not assume this result applies equally to every blood-pressure drug.

Make home readings useful

If the team asks for home readings, have them check your monitor and cuff size. The American Heart Association² recommends a validated automatic upper-arm monitor.²

Its preparation instructions include avoiding caffeine, smoking and exercise for 30 minutes, emptying your bladder, and resting for at least five minutes without talking or using your phone. Measure on a bare arm supported at heart level. Take two readings one minute apart, and record both.²

Ask the clinician how often to measure and when to send the record. Include medicine changes and symptoms in a separate note. A list of numbers without dates can be difficult to compare with the prescription history.

The American Heart Association² advises against stopping blood-pressure medicine on the basis of home readings without checking with a healthcare professional.²

Get instructions for problems before they happen

Ask what to do if you feel unwell, miss doses, or need to stop IBSRELA. Its Medication Guide says to stop taking it and call the doctor for severe diarrhea.¹ Tell the team managing enalapril about that change too.

For blood pressure above 180 systolic or 120 diastolic, repeat after at least a minute if there are no emergency symptoms; if still very high, contact a healthcare professional immediately. With chest pain, breathlessness, weakness, numbness, vision changes or difficulty speaking, call 911. Do not wait for it to fall.²

“The Visit Script” in Bloated by Dinner calls for every medicine and supplement, followed by a clear next-step question. Add: “Who is checking my blood pressure after this prescription starts, and when will we decide whether anything needs changing?”