Botox for the DAO muscle is the best treatment we offer at our Vancouver clinic to treat smile lines and downturned lip corners, otherwise known as the “permafrown.” When the outer corners of your mouth point downwards, it can create an unhappy expression even when you feel great. The cause of this downward movement is an overactivity of the Depressor Anguli Oris muscle (DAO), one of the many muscles we use to move our mouth when we speak, eat and make facial expressions. Luckily, Botox® offers a non-invasive option for relaxing and reducing the downward pull. Our highly trained, board-certified doctors are here to help you. 

Smile Lines Botox graphic vancouver sparrowmd


  • Length of Treatments: 30 minutes
  • Recovery Time: None
  • Onset of Action: 3-7 days after procedure. A follow-up appointment to fine-tune your results may be scheduled. 
  • Cost: Varies due to the severity of downturn and strength of DAO muscle
Smile Lines Botox graphic vancouver sparrowmd


The downturned lip treatment with DAO botox proves an effective solution for creating a mouth corner lift and a happier curve to your smile. With a gentle tap of the finger, our doctors can expertly inject botox into the DAO muscle. The DAO muscle activity causes your lip corners to pull downward and frown. When left unchecked over time, this downward force can contribute to the formation of smile lines or marionette lines, causing more signs of aging. DAO botox helps relax this downward force, softening the marionette smile lines and lifting the corners of the mouth. To learn more about where this is the right treatment for you, book a consultation with our team to explore your options.


At Sparrow MD, we offer different brands of neuromodulators approved by Health Canada that will counter the downward pull of the DAO muscle, which include: 

At Sparrow MD, we carry multiple brands of neuromodulators and will choose the best option for our patients. This can be discussed during the consultation process. 


In addition to Dysport® /Botox® treatments, our clients in Vancouver may choose to pair this treatment with the following for a more holistic approach to downturned lips correction: 

  • Dermal Fillers- to lift and restore volume by placing fillers in areas like the marionette lines
  • Ultherapy®- to aid in skin elasticity and skin tightening
  • Microneedling- to improve skin quality and tone by inducing collagen production
  • Medical Grade Skincare- to enhance the effects of facial treatments
Botox® to treat downturned lip corners


DAO botox, administered by our skilled medical professionals in Vancouver, offers temporary muscle relaxation for therapeutic and cosmetic purposes. With a track record of over 25 years, Botox stands as a safe and effective treatment. Though generally safe, there are potential side effects, such as temporary bruising, mild discomfort, swelling, or redness at the injection site. Botox® treatments are not recommended to anyone pregnant or nursing. For DAO Botox, side effects may include lip asymmetry or a more restricted smile. This is temporary, and a touch-up visit can usually correct any asymmetry.  At Sparrow MD, our team comprises highly trained physicians who possess the expertise and experience necessary to ensure you achieve optimal results, all while placing utmost emphasis on safety and effectiveness.


How long do the effects of DAO Botox last?

Botox® and other neuromodulators are temporary, typically lasting 3 to 6 months. The length will depend on the patient's DAO muscle strength and metabolism. Generally, our patients come back for maintenance treatments every 3 months. 

Is botox or dermal filler better to treat a down-turned smile?

To address a downturned smile, the choice between botox and dermal fillers depends on the extent of the downturn and the skin's elasticity. Botox relaxes the DAO muscle to lift the corners of the mouth, while dermal fillers like Juvederm® offer structural support by restoring lost volume. Fillers may be placed on the lips or marionette lines depending on desired outcomes. In some cases, a combination of both treatments may be optimal.

How many units of botox will I need to treat permafrown?

The units required will vary depending on individual muscle strength, the degree of the downturned smile and desired results. Doctors at our Vancouver clinic will start with a conservative dose of 6-10 units botox for DAO on both sides.

Does Botox® or dermal filler best treat smile lines?

At Sparrow MD in Vancouver, DAO botox is best for treating mild smile lines at the lower corners of the lips and preventing the development of deeper lines and folds. As we age, we begin to lose facial volume, which can contribute to the formation of deeper smile lines and skin folds. We recommend our patients to consider dermal filler treatments in the deeper folds of the nasolabial and marionette zone. Ultimately, dermal fillers and botox can be combined to achieve the best result. We encourage you to have an in-person assessment with one of doctors to help decide what would be best for you.