Side effects of Myrbetriq in the elderly
Historically, antimuscarinic drugs, such as Vesicare (oxybutynin), Detrol (tolterodine) and anticholinergic drugs, have been used to treat overactive bladder (OAB). However, these therapies have been shown to have side effects, such as dry mouth, drowsiness, constipation, dizziness, and confusion, as well as an increase in the risk of cognitive impairment and dementia, a side effect of considerable concern in older people.
Myrbetriq is the brand-name for an alternative treatment option manufactured by Astellas Pharma US, Inc. While Myrbetriq is generally well tolerated, there are some potential side effects that people should be aware of. The most common side effects of Myrbetriq include urinary tract infections, nausea, and headaches. Less common, but more serious side effects, can include irregular heartbeats, and palpitations.
Learn more about the side effects of Myrbetriq in the elderly and how to avoid them.
What is Myrbetriq (mirabegron)?
Myrbetriq contains mirabegron, a beta-3 adrenergic agonist as the active ingredient. It is used to treat an overactive bladder in adults. An overactive bladder is a condition where you feel the need to urinate often and sometimes suddenly. You may feel a combination of needing to urinate often (increased urinary frequency), needing to urinate suddenly (urinary urgency), or losing control of when you want to urinate (urinary incontinence). It is also used to treat neurogenic detrusor overactivity (NDO).
Mirabegron relaxes the muscles in the wall of your bladder (detrusor urinae muscle) helping to reduce the symptoms of an overactive bladder. It does this by attaching itself to areas on the surface of the muscles called β3-adrenergic receptors. These receptors are stimulated by mirabegron, starting a process that relaxes the bladder muscles.
Myrbetriq is available as 25 mg and 50 mg extended-release tablets.
The recommended starting dose of Myrbetriq is 25 mg once daily, alone or in combination with solifenacin succinate (Vesicare) 5 mg, once daily. Your dose of Myrbetriq may be increased to 50 mg once daily, based on its effectiveness and your ability to tolerate it.
Swallow the tablets whole with water, with or without food, do not chew, divide or crush. If you miss a dose, take the missed dose as soon as possible. If however, it’s been 12 hours or more since your dose was supposed to be taken, skip it and take the next dose at the normal time. Store Myrbetriq at room temperature, away from heat, moisture, and direct light.
Please read the prescribing information provided with this medicine for the drug information and patient information, and always speak with your healthcare provider for medical advice about any changes to your dose so they can monitor and evaluate your condition.
How effective is Myrbetriq?
Myrbetriq is FDA (Food and Drug Administration)-approved for the treatment of an overactive bladder. Approval is based on clinical studies, where Myrbetriq effectively treated symptoms of an overactive bladder within four to eight weeks, depending on the dosage.
What are the side effects of Myrbetriq in the elderly?
The most common side effects of Myrbetriq in clinical trials, compared to placebo include:
- Urinary tract infection (UTI)
- Headache, dizziness, nausea
- Fast heartbeat (tachycardia)
- Constipation, diarrhea
- Back pain
- Dry mouth
Myrbetriq can cause more serious side effects, including:
- Irregular heartbeat (atrial fibrillation), palpitations, affecting around 1 in 100 people
- Severe rise in blood pressure (hypertensive crisis), affecting around 1 in 1,000 people
If you experience any of these serious side effects, stop taking Myrbetriq and seek medical attention immediately. You are encouraged to report negative adverse events of prescription drugs to the FDA. Visit www.fda.gov/medwatch, or call 1-800-FDA-1088.
Myrbetriq drug interactions
Myrbetriq can interact with other medications including:
- Treatments for abnormal heart rhythm – propafenone or flecainide
- Beta-blockers – carvedilol, propranolol, metoprolol, timolol
- Drugs metabolized By CYP2D6 – desipramine
- Other medications for an abnormal heart rhythm – quinidine, sotalol, procainamide, ibutilide, flecainide, dofetilide, or amiodarone
- Certain blood thinners, such as warfarin, dabigatran etexilate
- Antipsychotic medicines – thioridazine, mesoridazine, haloperidol, or chlorpromazine
- Medications for allergic rhinitis
Before taking Myrbetriq, be sure to tell your doctor about all of the medications you are taking to ensure they are safe to take at the same time.
Myrbetriq warnings & precautions
Don’t take Myrbetriq if:
- Are allergic to the active ingredient mirabegron
- Have had an allergic reaction to any of the other ingredients in Myrbetriq
- If you have high blood pressure that is not controlled
- Are under 18 years of age
- Are pregnant or trying to become pregnant
Talk to your doctor before taking Myrbetriq if you:
- Take any other medications for an overactive bladder
- Have glaucoma
- Have other bladder problems (such as blockage)
- Have trouble emptying your bladder or have a weak urine stream
- Have any liver problems or kidney problems
- Have an ECG (heart tracing) abnormality called QT prolongation
- Are breastfeeding or plan to breastfeed – It is unknown if this medication passes into breast milk
You should always check with your doctor or pharmacist before taking any medication, including Myrbetriq, to make sure it is safe for you.
Other warnings you should know about
- Myrbetriq may increase your risk of urinary retention (trouble passing urine or not fully emptying the bladder), especially when used with another medicine (solifenacin succinate)
- Urinary retention has also been reported in patients with bladder outlet obstruction (BOO)
- Serious allergic reactions, called angioedema, which can be life-threatening and requires immediate medical attention have been reported. Stop treatment and get emergency medical help if you have signs of an allergic reaction (hives, trouble breathing, swelling of your face, lips, tongue, or throat)
How to avoid Myrbetriq side effects in the elderly
The best way to avoid side effects in older adults is to take Myrbetriq as directed by your doctor. Follow your doctor’s instructions carefully and do not take more or less than prescribed.
If you experience any side effects, talk to your doctor or pharmacist. They may be able to recommend ways to help reduce or prevent some of the side effects.
1. Stick to the recommended dosage
Take your prescribed dose of Myrbetriq that has been recommended by your healthcare professional. Do not take more or less than prescribed.
2. Drink plenty of fluids
If you have diarrhea with Myrbetriq may make you lose more fluids than usual if you have diarrhea. Drink plenty of fluids to avoid getting dehydrated.
3. Avoid alcohol
Alcohol does not affect how mirabegron works. Alcohol however can make your symptoms of urinary frequency and urgency worse.
4. Know the signs and symptoms of Myrbetriq side effects
Signs and symptoms of side effects include hypertension, nasopharyngitis, and urinary tract infection. If you experience any of these symptoms talk to your doctor.
5. Tell your doctor about all medications you’re taking
Be sure to tell your doctor about all other medications you’re taking, including over-the-counter drugs, vitamins, and herbal supplements, as they may interact with Myrbetriq.
6. Get regular medical checkups
If you have an overactive bladder it is important to get regular medical check ups and monitor your medical conditions. Your doctor will monitor your side effects and may adjust your dose of Myrbetriq as needed.