To Tox or not to Tox?

Where  –  is the question.

The widespread emergence of botulinum neurotoxins in the field of aesthetics is actively being researched and on the precipice of larger applications. Despite the relative novelty of the field, a lot has already been determined with regards to its effectiveness in different applications. In continuation of the overview on botulinum toxins, this article presents a lens into the general guidelines and treatment recommendations pertaining to facial injection and its associated topography.

General Guidelines

A couple of general guidelines to minimize discomfort of the patient include the use of topical anesthetics or the application of ice packs to the skin prior to injection. To further minimize bruising, patients should discontinue any medications that interfere with the stopping of blood flow (hemostasis) 10 to 14 days prior to injection, and the smallest gauge needle should be used. The spread of injected BTA can be up to 3 cm from the injection site, so the concentration of the substance should be taken into consideration when the desire is to increase diffusion – or more often limit it when targeting a highly specific area

Upper Face

Due to less volume loss over time than other parts of the face and the development of rhytides being the predominant age marker, treatment of the area generally yields good to excellent results.

Transverse Forehead Rhytides

Two main considerations for success in the treatment of transverse forehead rhytides are the comparative presence of dynamic versus static rhytides, and review of the general forehead anatomy of the patient as pertaining to their muscle strength, muscle orientation, and brow height, to name a few. 

Women: 10-20 Units

Frontalis muscle

  • Brow asymmetry should be noted and discussed with the patient before treatment
  • Patients should forcefully elevate their brow to assess the strength and location of the dynamic rhytides
  • Frontalis is typically injected in 4 to 12 sites
  • Take care to stay at least 1 to 2 cm above the supraorbital rim to avoid brow or eyelid ptosis

Men: 16-24 Units

Glabellar Region

FDA-approved aesthetic use of BTA in 2002 was for the glabellar region and it remains the most frequent indication for its use. Treatment of glabellar rhytides with botulinum toxin type A can improve quality of life and may reduce negative moods – a high level of satisfaction has been shown even 4 months after treatment.

20 Units divided among 5 injection sites (on-label)


Women up to 30 units


Men up to 40 units

Paired corrugator supercilii muscles

Central procerus muscle

  • Ask patient to frown maximally to estimate muscle strength, location, and size
  • Any asymmetry should be carefully evaluated 
  • 5-point V pattern, with 2 injection sites in each corrugator and 1 in the central procerus
  • Injections should be kept a minimum of 1 cm above the orbital rim to avoid diffusion into the levator palpebrae superioris muscle, causing iatrogenic ptosis
  • Injections at the tail of the corrugators should be kept superficial to avoid diffusion as above.

Brow Lift

Often combined with the treatment of the glabellar complex and frontalis, the lateral brow lift is most often performed as a component of treating the rest of the face. Glabellar complex treatment alone has also been found to lift the lateral brow by as much or more than the medial brow.

2 to 5 Units

Orbicularis oculi muscle

  • Chemically weakening the lateral fibers of the preorbital orbicularis oculi can result in lateral brow elevation by 2 to 4 mm
  • Injected intradermally, just beneath the tail of the lateral brow

Lateral Orbital Region (Crow’s Feet)

A well documented use, BTA successfully softens the appearance of crow’s feet (lateral canthal lines), the result of hyperkinetic orbicularis oculi muscles.

Starting Doses



8-10 Units

Orbicularis oculi muscle (targeting the preorbital region)

  • Just one element of a multifactorial periorbital aging process, the treatment cannot single handedly restore a youthful appearance but with careful selection of the patient (no excessive skin damage/static rhytides) and treatment, great results can be had
  • 3 equal injections of 2 to 4 U placed superficially (intradermal), producing a visible bleb beneath the skin at each site
  • The middle injection is placed in line with the lateral canthus, and the remaining 2 injections are placed 8 to 10 mm above and below this point.
  • Injection points should be kept at least 1 cm away from the orbital rim


12-16 Units


Treatment with botulinum toxin has a more limited role than dermal fillers or surgical resuspension because of volume loss and descent more prevalent in the area.


Oblique Nasal Sidewall Rhytides (Bunny Lines)

Caused by hyperactivity of the transverse portion of the nasalis muscle

2-5 Units per side

Nasalis muscle: paired structure, consisting of an alar and transverse portion

  • Injection in each muscle belly or a single, central injection
  • Injection sites should be kept high on the nose and superficial to avoid excessive paralysis of the deeper and more inferior levator labii superioris and levator labii alaeque nasi, important elevators of the upper lip

Upper Lip

Although it can be exacerbated by activities such as smoking and sun exposure, vertical perioral rhytides are a universal marker of increasing age. Although BTA can improve dynamic (and to some extent, static) rhytides, they are often used in conjunction with dermal fillers  to improve the contour and volume loss in the lip. 

4-6 Units

Orbicularis oris muscle

  • Injections should be kept medial to a vertical line dropped from the lateral nasal ala to the upper lip vermillion
  • Small aliquots (1–2 U of Botox Cosmetic each) are injected between 2 to 4 symmetric sites along the superior vermillion border
  • Likewise on the lower lip, injections should similarly stay at least 1 cm medial to the oral commissures and should mirror or bisect the upper lip injections
  • Patient should be advised that they may have difficulty with activities requiring pursed lips after treatment

Lower Face and Neck

As mentioned with the mid-face, treating aging-related changes in the lower face and neck are more successfully done with the restoration of volume and resuspension of descended tissues, although several aesthetic indications for treatment with BTA exist.

Depressor Anguli Oris

A downturn in the corner of the mouth, often causing an angry or sad look, is created by the contraction of the depressor anguli oris (DAO). BTA treatment of these muscles can reduce the downward pull and provide a subtle lift, reducing the DAO contraction and de-accentuating the melomental fold.

2-5 Units

Depressor anguli oris

  • An area with a lot of interdigitation of depressors, elevators, and sphincters – accurate placement of BTA is essential in avoiding asymmetry, phonation or impaired speech/oral competence
  • The patient should be asked to clench their jaw, causing a palpitation of the anterior border of the masseter
  • The DAO muscle can be safely injected 1 cm medial from this point, 2 to 3 mm above the inferior border of the mandible
  • Injections should be kept at least 1 cm lateral to the lateral oral commissure


The appearance of wrinkling or dimpling of the chin (referred to as peau d’orange), this is most often visible when the facial muscles are engaged and is not often an indication.

5-10 Units

Mentalis muscle

  • A single injection in the midline at the origin of both bellies of the mentalis or, more commonly, an injection into each muscle belly where treatment points are located 2 mm above the inferior border of the mandible and approximately 5 mm to the left or right of midline
  • In either pattern, injections should be kept deep to avoid inadvertent spread to the overlying orbicularis oris and depressor labii inferioris muscles

Masseteric Hypertrophy

Creating a square or “masculine” appearance to a female face, the enlargement of the masseter can be treated with BTA although genetic and habitual components are involved in the pathogenesis.

Starting Doses


30-35 Units


  • Treatment of the masseter with BTA is different from other areas in that the primary indication is to induce muscle atrophy as oppose to limit muscle contractions (thus alleviating skin wrinkling)
  • Avoid excessive paralysis, weaking mastication
  • The location of the surrounding musculature, most notably the risorius muscle and zygomaticus muscle, is also important as it can alter the kinetics of the angle of the mouth, causing facial asymmetry

Platysmal Banding

The aging of the neck is a continuing challenge to aesthetic practitioners, and many issues associated with aging require surgical intervention. However, BTA can play a role in rejuvenation with the improvement of vertical platysmal banding and horizontal rhytides.

~ 30-40 Units 


Important to keep to less than 50 Units per session


(with significant variability reported in literature) 

Platysma Muscle

  • BTA injection in lieu of platysmaplasty is a safe and effective procedure
  • Patients should be asked to contract the platysma muscle by showing the examiner their bottom teeth, allowing the grasp of each band between the thumb and index finger of the nondominant hand while injecting
  • Direct injections into the bands in 3 to 5 sites, at 1 cm intervals along the muscle are suggested, with 4 to 5 U per injection site
  • Care must be taken to inject specifically into the bands, in the deep dermal layer
  • Diffusion of BTA to the strap muscles or deeper muscles of the neck can cause dysphagia, dysphonia, dysarthria, or life-threatening breathing difficulties


Overall, the aesthetic uses of injectable botulinum toxins in the face are extensive and patient satisfaction with treatment is very high. For both practitioners and patients, the goal of treatment has shifted from an ironed, “frozen” look, to a softer one preserving natural expression through the dampening of muscular activity. Treatment has overall proven more effective on dynamic facial rhytides as opposed to static ones, and it will not necessarily serve as a substitute for other facial procedures. As always, clear communication with realistic, individually assessed expectations and goal setting with the patient are paramount for successful results.


Gart, Michael & Gutowski, Karol. (2016). Overview of Botulinum Toxins for Aesthetic Uses. Clinics in Plastic Surgery. 43. 10.1016/j.cps.2016.03.003.