DAO Botox typically lasts 3 to 6 months, with most people seeing their best results for about 3 to 4 months before the effect gradually fades. The DAO, or depressor anguli oris, is the muscle that pulls the corners of your mouth downward, and small doses of Botox can relax it enough to create a subtle lift at the mouth corners. Here’s what to expect from the timeline, what affects how long your results hold, and what makes this injection area unique.
What DAO Botox Does
The depressor anguli oris is a small muscle that runs from your jawline up to the corner of your mouth. Its job is to pull the mouth corner downward, which is useful for frowning but also contributes to a resting “sad” or “displeased” expression as the muscle strengthens with age. When Botox is injected into the DAO, it weakens that downward pull, allowing the opposing muscles (the ones that lift your mouth corners) to work unopposed. The result is a subtle upward turn at the corners of your mouth, sometimes called a “lip flip” or “mouth corner lift.”
This isn’t a dramatic change. Most people describe it as looking less tired or less stern at rest, rather than looking like they’ve had work done.
When Results Appear and Peak
You won’t see the full effect on the day of your injection. Botox generally begins working within 2 to 5 days, with visible changes starting around the one-week mark. The average onset across injection sites is roughly 6 to 7 days, though some people notice subtle changes as early as day 2 or 3.
Peak results typically arrive around 5 to 6 weeks after treatment. This is when the muscle is at its most relaxed and the lift at the mouth corners is most pronounced. If you’re evaluating your results, that 5- to 6-week window is the best time to assess what the treatment has done for you.
How Long the Lift Lasts
For most people, DAO Botox holds its effect for 3 to 4 months at peak performance. Some people get up to 6 months before the muscle fully regains its pulling strength. After that window, the treated muscle gradually begins contracting again, and the mouth corners will slowly return to their pre-treatment position.
The fade-out is gradual rather than sudden. You won’t wake up one morning with the effect gone. Instead, you’ll notice over a few weeks that the downward pull is creeping back. Many people schedule their next appointment around the 3- to 4-month mark to maintain a consistent look, though some stretch it to 5 or 6 months depending on how quickly their results wear off.
Factors That Shorten or Extend Results
Not everyone metabolizes Botox at the same rate, and several factors influence how long your DAO treatment lasts.
- Exercise intensity: Vigorous physical activity raises your overall metabolism, which can shorten how long Botox stays effective. People who do high-impact workouts like CrossFit or long-endurance exercise tend to burn through Botox faster. Research confirms that higher levels of physical activity exert a measurable negative influence on how long the muscle-relaxing effect persists.
- Muscle strength: Stronger, more active facial muscles can overpower the Botox sooner. If you’re someone who uses your lower face expressively (lots of talking, singing, or animated facial expressions), you may find the effect wears off on the shorter end of the timeline.
- Individual metabolism: Some people simply process botulinum toxin faster than others, regardless of lifestyle. If you’ve had Botox elsewhere on your face and noticed it wearing off quickly, the same pattern will likely apply to DAO injections.
- Dose used: DAO injections use relatively small amounts of Botox compared to areas like the forehead. The dose your provider chooses can affect duration, though there’s a ceiling: too much product in this area increases the risk of side effects rather than extending the timeline.
Why DAO Injections Require Precision
The mouth corner area is one of the trickier spots to inject. The DAO muscle overlaps with several neighboring muscles, including one that controls your lower lip and others involved in smiling and pulling the mouth sideways. These muscles sit close together and partially overlap, which means even a small error in depth or placement can affect the wrong muscle.
The most common concern is asymmetry. If Botox diffuses into the neighboring lower lip muscle, it can weaken your ability to pull your lower lip down on one side, creating an uneven smile. This is temporary (it fades as the Botox wears off), but it’s the main reason DAO injections are considered an advanced technique. Anatomical studies have found significant variation between individuals in how these muscles overlap, which is why experienced injectors typically start with conservative doses and adjust at follow-up visits.
If you’re getting DAO Botox for the first time, expect your provider to use a small dose and potentially bring you back in two weeks to assess the result before adding more.
Maintaining Results Over Time
Because the effects are temporary, maintaining a lifted mouth corner appearance requires regular treatments. Most people settle into a schedule of every 3 to 4 months, though your ideal interval depends on how quickly you metabolize the product. Some providers recommend slightly more frequent treatments in the first year to keep the muscle consistently relaxed, then spacing appointments further apart as the muscle gradually weakens from repeated treatment.
There’s no evidence that repeated Botox injections to the DAO cause permanent changes to the muscle, but over time many people find their results last a bit longer between sessions. This is a common pattern with Botox across all treatment areas: the muscle becomes conditioned to a lower level of activity, and each round of treatment may hold slightly longer than the last.