Key takeaways:
Myrbetriq (mirabegron) and oxybutynin are first-choice medications for treating overactive bladder. They work differently but offer similar health benefits.
Since oxybutynin is an anticholinergic medication, it tends to have more side effects than Myrbetriq. Drowsiness and dry mouth are common ones. Myrbetriq can raise blood pressure.
Myrbetriq and oxybutynin are both available as brand-name and generic medications. GoodRx can help make your prescription more affordable.
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Some of the most common health problems — such as overactive bladder (OAB) — can be the hardest to talk about. Classic OAB symptoms include feeling sudden urges to pee, accidentally leaking urine, or urinating too frequently, especially at night.
Lifestyle changes are good starting points for managing OAB. Pelvic floor exercises and limiting fluids before bedtime are a couple of examples. But sometimes you need to take an OAB medication to help manage your symptoms.
Myrbetriq (mirabegron) and oxybutynin are two common medication options. They’re similar in many ways, but there are several distinctions between them. Here, we’ll discuss five main differences between Myrbetriq versus oxybutynin.
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1. Myrbetriq and oxybutynin are FDA approved for overactive bladder, but they work differently
Myrbetriq and oxybutynin are FDA approved to treat OAB in adults. They’re both considered first-choice medications for OAB. But Myrbetriq and oxybutynin work differently for OAB.
With OAB, the bladder muscles contract before the bladder is full. This can cause accidental or frequent urination.
Myrbetriq treats OAB by stimulating beta-3 receptors in the bladder. These proteins are chemical sites that the medication attaches to. When activated, the proteins relax the bladder muscles and help the bladder hold more urine.
Oxybutynin is known as an anticholinergic (antimuscarinic) medication. It works by blocking the chemical acetylcholine from binding to its receptors. In turn, this relaxes your bladder muscles to help lessen OAB symptoms.
2. Myrbetriq and oxybutynin dosages are different for overactive bladder
Myrbetriq is an oral medication that comes as an extended-release (ER) tablet for OAB. The starting dosage is 25 mg by mouth once daily, and it can be raised to 50 mg daily after about 4 to 8 weeks (1 to 2 months) if needed.
But oxybutynin comes in a variety of forms. Oxybutynin’s recommended dosages are based on which version you’re taking.
| Oxybutynin formulations and dosages | Available as generic? | Available over the counter? | Starting dose |
|---|---|---|---|
| ER oral tablet 5 mg, 10 mg, 15 mg |
Yes | No | 5 or 10 mg by mouth once daily |
| Immediate-release (IR) oral tablet 5 mg |
Yes | No | 5 mg by mouth 2 to 3 times daily |
| Oral liquid 5 mg / 5 mL |
Yes | No | |
| Oxytrol patch for men 3.9 mg / 24 hr |
No | No | 3.9 mg / 24 hour patch applied to the skin every 3 to 4 days |
| Oxytrol for Women patch 3.9 mg / 24 hr |
No | Yes | 3.9 mg / 24 hour patch applied to the skin every 4 days |
3. Myrbetriq and oxybutynin are similarly effective for overactive bladder, but they aren’t identical
Research suggests that Myrbetriq and oxybutynin can reduce OAB symptoms compared with a placebo (a pill with no medication in it). When compared with each other, they have a similar clinical benefit for OAB. One medication isn’t considered more effective than the other.
It’s recommended to try oxybutynin or Myrbetriq for at least 1 to 2 months before determining if it works. If you have bothersome symptoms after this time period, a healthcare professional may raise your dose. Other options include adding on another medication or trying a different one.
Can you take Myrbetriq and oxybutynin together?
Yes, if needed. Because they work differently, Myrbetriq and oxybutynin can be taken together. Combination therapy can be useful if you still have symptoms after taking the highest-tolerated dose of one medication.
But Myrbetriq has been studied the most with the anticholinergic medication solifenacin. Research shows the combination helps improve OAB symptoms.
4. Oxybutynin may cause more side effects than Myrbetriq
Like all medications, Myrbetriq and oxybutynin can cause side effects. But oxybutynin tends to cause more of them.
Oxybutynin blocks cholinergic receptors throughout the body, not just the bladder. This can lead to unintentional side effects, mentioned below. Mybetriq is a more selective medication for receptors in the bladder.
This chart compares Myrbetriq and oxybutynin side effects.
Shared side effects | Additional Myrbetriq side effects | Additional oxybutynin side effects |
|---|---|---|
Headache | Elevated blood pressure | Dry mouth |
Constipation | Urinary tract infection (UTI) | Drowsiness |
Fatigue | Common cold symptoms | Blurry vision |
Diarrhea | – | – |
Dizziness | – | – |
Because of its high side effect potential, it’s recommended to limit oxybutynin’s use in older adults.
But the ER version is released more slowly than the IR version. This steadier release tends to cause fewer side effects. So the ER form is usually preferred over the IR form.
Keep in mind that side effects can vary by person and dose.
Serious side effects of Myrbetriq and oxybutynin
In addition, more serious risks are also possible. One of these is difficulty emptying your bladder (called urinary retention). This can happen with either medication.
You should also be cautious when taking oxybutynin if you have certain medical conditions, since the medication can make them worse:
Movement problems in your stomach or intestines
Myasthenia gravis (autoimmune disease causing muscle weakness)
Myrbetriq and oxybutynin potentially cause swelling of the face, lips, or throat (called angioedema). This is rare, but if you experience angioedema symptoms, call 911 right away.
5. Myrbetriq and oxybutynin interact with different medications and supplements
Several medications and supplements don’t mix well with Myrbetriq and oxybutynin. Ask your prescriber or pharmacist if any medications or supplements you take could interact with Myrbetriq or oxybutynin.
Oxybutynin interactions
Some medications can cause oxybutynin to build up in the body. This can increase the risk of side effects. Other medications don’t affect oxybutynin levels but can worsen side effects when taken together.
Watch out for these oxybutynin interactions:
Other anticholinergic medications, such as diphenhydramine (Benadryl) and glycopyrrolate (Robinul)
Azole antifungals, such as oral ketoconazole
Medications that cause constipation, such as iron supplements and oxycodone (Roxicodone, OxyContin)
Medications that cause dry mouth, such as benzodiazepines and quetiapine (Seroquel)
Oxybutynin also interacts with metoclopramide (Reglan, Gimoti), a medication that treats gastroparesis (delayed stomach emptying) from diabetes. Oxybutynin can make metoclopramide less effective by slowing down digestion.
Myrbetriq interactions
Myrbetriq doesn’t have many serious interactions. But it does block a specific liver enzyme (called CYP2D6). This means medications broken down by this enzyme could build up in the body if you take them with Myrbetriq.
Examples of these Myrbetriq interactions include:
Codeine
Tramadol (ConZip)
Metoprolol (Lopressor, Toprol XL)
Clozapine (Clozaril)
Amitriptyline
Thioridazine
Flecainide
Propafenone
Your healthcare team may monitor you more closely and possibly lower your dosage of the above medications if you’re taking them with Myrbetriq.
Good to know: Myrbetriq also interacts with the heart medication digoxin (Lanoxin). It can raise digoxin blood levels. Your prescriber may recommend a lower digoxin dosage if you’re taking it with Myrbetriq. They may also check your digoxin level with a blood test to make sure it isn’t too high.
Myrbetriq and oxybutynin alternatives
If Myrbetriq or oxybutynin isn’t a good fit, other treatment options are available.
It helps to know which medication class these alternatives belong to. If you can’t take Myrbetriq or oxybutynin, you may also need to avoid other medications in the same class.
| Anticholinergics, similar to oxybutynin | Beta-3 agonists, similar to Myrbetriq | Other |
|---|---|---|
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|
|
How to save on Myrbetriq and oxybutynin
There are ways to save on Myrbetriq and oxybutynin. Both are available as brand-name medications. But you can also find them as lower-cost generics. GoodRx can help you navigate ways to save on your prescription.
Save with GoodRx: GoodRx can help you save over 50% off the average retail price of the generic version of oxybutynin or Myrbetriq. A month’s supply of generic oxybutynin at certain pharmacies costs as little as $21.22 with a free GoodRx discount. A similar amount of generic Myrbetriq may cost as little as $117.62.
Save with a copay savings card: If you have commercial insurance and meet eligibility requirements, you can save up to $70 per month on brand-name Myrbetriq using a savings card from the manufacturer.
Frequently asked questions
The best OAB medication for you will likely depend on a variety of factors, such as your age, personal preferences, and budget.
Myrbetriq and oxybutynin are similarly effective. But oxybutynin causes more side effects. On the other hand, oxybutynin costs less than generic Myrbetriq. Together with your healthcare team, you can decide which option is best.
People with very high blood pressure shouldn’t take Myrbetriq. That’s because Myrbetriq can potentially raise your blood pressure. A healthcare professional will likely recommend a different OAB medication if your blood pressure is well above your target range.
Separately, if you’ve ever experienced an allergic reaction to Myrbetriq, it’s best to avoid it moving forward.
Older adults — especially people ages 65 and older — are more sensitive to the side effects of anticholinergic medications like oxybutynin. In this age group, side effects such as confusion and delirium are especially concerning because they can raise the risk of falls.
Myrbetriq and Gemtesa tend to have fewer side effects than oxybutynin because of the way they work. Certain anticholinergic medications — like solifenacin and darifenacin — are more selective for the bladder than the rest of the body. That’s why they typically cause less side effects than oxybutynin.
The best OAB medication for you will likely depend on a variety of factors, such as your age, personal preferences, and budget.
Myrbetriq and oxybutynin are similarly effective. But oxybutynin causes more side effects. On the other hand, oxybutynin costs less than generic Myrbetriq. Together with your healthcare team, you can decide which option is best.
People with very high blood pressure shouldn’t take Myrbetriq. That’s because Myrbetriq can potentially raise your blood pressure. A healthcare professional will likely recommend a different OAB medication if your blood pressure is well above your target range.
Separately, if you’ve ever experienced an allergic reaction to Myrbetriq, it’s best to avoid it moving forward.
Older adults — especially people ages 65 and older — are more sensitive to the side effects of anticholinergic medications like oxybutynin. In this age group, side effects such as confusion and delirium are especially concerning because they can raise the risk of falls.
Myrbetriq and Gemtesa tend to have fewer side effects than oxybutynin because of the way they work. Certain anticholinergic medications — like solifenacin and darifenacin — are more selective for the bladder than the rest of the body. That’s why they typically cause less side effects than oxybutynin.
The bottom line
Overactive bladder (OAB) symptoms can be uncomfortable and disruptive to daily life. But medications are available to help. Both Myrbetriq (mirabegron) and oxybutynin are effective medications for treating OAB. Oxybutynin tends to have more side effects because of how it works in the body. Myrbetriq and oxybutynin interact with different medications. If you have questions or concerns about either medication, ask your pharmacist or prescriber for more information.
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References
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