Key takeaways:
Myrbetriq (mirabegron) and oxybutynin are first-choice medications for treating overactive bladder.
These two medications work differently, but they offer similar health benefits. You might also consider cost, dosing, and side effects when comparing the two.
Myrbetriq and oxybutynin are both available as brand-name medications. But you can also find oxybutynin as a lower-cost generic. 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 symptoms of OAB are feeling sudden urges to urinate, accidentally leaking urine, or urinating too frequently, especially at night.
It’s pretty common, too. Over 33 million U.S. adults live with OAB. This might even be an underestimate because many people are hesitant to talk about it. And while it can happen to anyone, women and older adults are the most commonly affected.
Thankfully, OAB is treatable. It’s not a disease or normal part of aging that you have to live with. Behavioral therapies — such as bladder training and pelvic training exercises (like kegels) — are go-to choices when possible. But if additional support is needed, many over-the-counter (OTC) and prescription medications can also be used to treat OAB.
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Here, we’ll compare the pros and cons of two common OAB medications — Myrbetriq versus oxybutynin.
What is Myrbetriq?
Myrbetriq (mirabegron) is a first-choice medication for OAB. It’s FDA-approved to treat OAB symptoms of urinary urgency, frequency, and leakage in adults. It’s also approved to treat a condition called neurogenic detrusor overactivity in children ages 3 and older.
How does Myrbetriq work for overactive bladder?
In OAB, the bladder muscles contract before the bladder is actually full. This can cause accidental or frequent urination. Myrbetriq — a beta-3 agonist — works against this. It activates beta-3 receptors, which are chemical binding sites in the bladder that the active ingredient of Myrbetriq can attach to. This relaxes the surrounding muscles and helps store more urine.
What is oxybutynin?
Oxybutynin is another first-choice medication for treating OAB. Similar to Myrbetriq, it’s also FDA-approved to treat OAB symptoms of urinary urgency, frequency, and leakage in adults. An extended-release (ER) version of oxybutynin is also approved to treat OAB caused by a neurological condition (like spina bifida) in people ages 6 and older.
How does oxybutynin work for overactive bladder?
Oxybutynin works differently than Myrbetriq — it interferes with muscarinic receptors.
Normally, stimulating these receptors causes your bladder to contract. This allows you to urinate. By blocking these receptors, antimuscarinic medications like oxybutynin can reduce bladder contractions and help control symptoms of OAB. Antimuscarinics are a type of anticholinergic medication.
How are Myrbetriq and oxybutynin dosed and given?
Myrbetriq is an oral medication that only comes in an ER formulation, so it’s taken once daily. The starting dose is 25 mg daily and it can be raised to 50 mg daily after about 1 to 2 months, if needed.
On the other hand, oxybutynin’s dosing is a bit more complicated. The table below helps summarize the details.
| Oxybutynin formulations and dosages | Available as generic? | Available OTC? | 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/5mL |
Yes | No | |
| 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 |
| Patch for women 3.9 mg/24 hr |
No | Yes | 3.9 mg/24 hour patch applied to the skin every 4 days |
How effective are Myrbetriq and oxybutynin for overactive bladder?
Research suggests that both Myrbetriq and oxybutynin can reduce OAB symptoms when compared to a placebo (a pill with no medication in it). When compared to each other, they have a similar clinical benefit and can potentially raise your bladder’s capacity by about 20%. 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 they work. If you still have bothersome symptoms after this time period, your healthcare provider may recommend trying two or more medications at the same time, or a different medication altogether.
Can you take Myrbetriq and oxybutynin together?
Yes, if need be. Because they work differently, antimuscarinics and beta-3 agonists can be taken together as combination therapy. Combination therapy can be useful if you still have symptoms after taking the highest tolerated dose of one medication.
However, the strongest evidence for combination therapy supports using Myrbetriq with a different antimuscarinic medication, called Vesicare (solifenacin). The evidence for using Myrbetriq and oxybutynin together is not strong enough for health experts to directly recommend using them together. But this may change in the future with more research.
What are the known side effects of Myrbetriq and oxybutynin?
Both medications can cause side effects, but oxybutynin tends to cause more of them.
Oxybutynin may block muscarinic receptors in other places in the body, not just the bladder. This can lead to unintentional side effects, mentioned below. On the other hand, Mybetriq is a more selective medication for receptors in the bladder. It has a lower rate of side effects than oxybutynin.
| Side effect | Myrbetriq ER | Oxybutynin ER |
|---|---|---|
| Elevated blood pressure | 7%-11% | – |
| Urinary tract infection (UTI) | 3%-4% | – |
| Dry mouth | – | 35% |
| Headache | 2%-3% | 8% |
| Constipation | 2% | 9% |
| Fatigue | 1% | 3% |
| Diarrhea | 1% | 8% |
| Drowsiness | – | 6% |
| Blurry vision | – | 4% |
Due to its high side effect potential, it’s recommended to limit oxybutynin’s use in older adults. Because oxybutynin ER is released more slowly in the body than IR, it causes fewer side effects. Oxybutynin ER is usually preferred over oxybutynin IR when possible.
Also, keep in mind that side effects can vary by person and by dose.
What are the serious side effects of Myrbetriq and oxybutynin?
In addition to what’s mentioned above, more serious side effects are also possible. Myrbetriq and oxybutynin could potentially cause swelling of the face, lips, tongue, or throat (called angioedema) or an inability to empty your bladder (called urinary retention). Contact your healthcare provider right away if you experience either of these rare but serious side effects.
Additionally, it’s important to be cautious with using oxybutynin if you have the following conditions, since it could make them worse:
Narrow-angle glaucoma
Movement problems in your stomach or intestines
What interactions do Myrbetriq and oxybutynin have?
Oxybutynin can interact with potassium supplements. If you take the two together, there’s a higher risk of experiencing ulcers or bleeding in your stomach. This is because oxybutynin can slow down movement in the stomach or intestine and cause the potassium supplements to stick around for too long.
Also, since oxybutynin is a type of anticholinergic medication, it shouldn’t be taken with other anticholinergic medications (such as glycopyrrolate or tiotropium). Combining these can worsen side effects.
Myrbetriq doesn’t have many serious interactions, but a few notable ones are listed here. It acts as an “inhibitor” medication that affects the concentration of medications like these in your body:
Check with your healthcare provider or pharmacist to see if any medications or supplements you take could interact with Myrbetriq or oxybutynin.
How to save on Myrbetriq and oxybutynin
There are many ways to save on Myrbetriq and oxybutynin. Both are available as brand-name medications. But you can also find oxybutynin as a lower-cost generic. GoodRx can help you navigate many ways to save on your prescription.
Save with GoodRx. GoodRx can help you save over 65% off the average retail price of the generic version of oxybutynin. Generic oxybutynin’s price at certain pharmacies is less than $25.49 with a free GoodRx discount.
Save with patient assistance programs. If you’re uninsured or underinsured, you may be eligible for Myrbetriq’s patient assistance program, which offers the medication free of cost.
Save with a copay savings card. If you have commercial insurance and meet eligibility requirements, you can save up to $70 per month on Myrbetriq using a savings card from the manufacturer.
How do healthcare providers decide which medication to prescribe?
Myrbetriq works as well as oxybutynin, and it causes fewer side effects. But its cost can be a barrier. Because of this, your healthcare provider may suggest trying oxybutynin first. But if you have side effects from oxybutynin, or it doesn’t work well, you may be advised to try Myrbetriq.
The bottom line
OAB symptoms can be uncomfortable and disruptive to daily life, but medications are available to help. Both Myrbetriq and oxybutynin are FDA-approved to treat OAB. Oxybutynin is available as a generic oral medication and as a brand-name patch, while Myrbetriq is only available as a brand-name oral medication. If you have any questions or concerns about either medication, make sure to reach out to your pharmacist or healthcare provider for more information.
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References
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