3 Common Mistakes when injecting Botulinum Toxin

Ever had a patient with a heavy brow after Botox? Worried about eyelid ptosis? Puffy eyes after toxin?

Botulinum Toxin-A was first used cosmetically in the mid-1980’s, and its usage has exploded. Of almost 10 million treatments performed by members of the American Society for Dermatologic Surgery in 2015, 1.8 million of these were toxin procedures.

However, due to lack of standardised training, pharma company-led marketing and unregulated practice; there is significant variance in outcomes from toxin treatments.

This article reviews the three most common mistakes, and how to avoid them.

Mistake 1: Over-treating the frontalis

The frontalis is the hardest area of the face to treat with toxin. It is the only elevator muscle in the forehead and accurate treatment will be required in order to achieve natural results. There are a few points to consider when treating the frontalis:

– The dose will need to be adjusted depending on the size of the forehead and the dynamic lines. For example, in patient with a long forehead, two rows of injections may be required to cover the area sufficiently. And in patients with small and short foreheads, a smaller dose is advised, especially for the initial treatment.

– Men usually will require a higher dose of toxin when compared to women.

– If the three depressor muscles (orbicularis oculi, corrugator and procures) are not treated at the same time, this may result in heavy looking eyebrows and potentially brow ptosis.

– Patients who present with increased skin laxity in the upper eyelid and hooded eyelids will need to be treated with caution. Injections would need to be placed highly (at least 3 cm above the orbital rim). And in cases where the frontalis muscle is over-compensating for the increased skin laxity and is required in the opening of the eyes, treatments in the frontalis muscle with toxin should be avoided.

Additionally, when treating the tail of the corrugator muscle, ensure the injection is placed superficially. The muscle inserts into the skin laterally, and superficial placement will avoid inadvertent treatment of the frontalis.

Mistake 2: Believing the myths

Many post-treatment instructions are highly anecdotal and speculative. For example, there is no evidence that keeping the head elevated for 6 hours post treatment will reduce the chance of adverse events. In fact, most of the toxin is inside the synaptic vesicles within 5 to 10 minutes after binding. There have been no demonstrated alterations of effect from massaging or not massaging the areas injected post-treatment.

The only study showing that muscle activity by a patient after aesthetic treatment can be beneficial, is by Wei et al., which demonstrated that masseteric muscle atrophy was significantly higher in patients who clenched their chewing muscles for 2 hours per day post-treatment (so recommending chewing gum after masseter toxin would be sound clinical advice – although this evidence is very preliminary).

In summary, the below common pieces of aftercare advice have no evidence:

– “don’t rub the area after treatment”

– “avoid applying make-up after treatment”

– “do not lie flat after treatment”

– “avoid air travel after treatment”

In our aftercare advice, we still recommend not rubbing the treated areas and to avoid applying makeup directly over the injection sites, because these make sense to us.

Mistake 3: Ignoring the Mid and Lower Face

Toxin is fantastic for dynamic lines in the upper third. However, as you gain confidence, don’t be afraid to explore some of the more unusual applications of botulinum toxin in the mid and lower face. 

Note – these are off-label treatments.

We believe the following three muscles are the most useful muscles to target in the lower face:

Depressor Angulae Oris

This muscle is partially responsible for causing the corners of the mouth to turn downwards at rest.

Two to three units per side at mid-muscle height, in the subcutaneous plane, will result in effective treatment. Importantly, avoid the depressor labii inferioris, which lies deeper and more medially. 

Levator labii superioris alaeque nasi and nasal tip droop

The elevator labii superiors alaeque nasi originates from the frontal process of the maxilla and inserts into the skin of the nasal ala and the superior aspect of the lip. This muscle is responsible for elevating the superior lip and the nasal ala.

It also works alongside the depressor septi nasi muscle to open the nostrils.

Gummy smiles can be effectively treated with botulinum toxin. 1 unit right at the peak of the nasolabial fold, in the subcutaneous plane, will often be all that is required. This treatment often requires an adjustment dose.

Note – recent use of filler to affect the muscle action of this muscle can be equally, if not more effective at treating a gummy smile. This process is called myomodulation, and is outside the scope of this article.

Nasal tip droop:

Musculature around the nose is complex and can be divided into the elevators, depressors, dilators, and constrictors.

The Levator labii superioris alaeque nasi belongs to the elevator category. The clue is in the name! In fact, the latin translation is ‘elevator of the upper lip accompanying the nose’. Injecting 3 units in each LLSAN muscle and 5 units in the depressor septi nasi muscle will prevent the nasal tip from dropping, especially when the patient is smiling.


Whilst most of the muscles treated by botulinum toxin are muscles of facial expression, the masseter is a muscle of mastication. It is a thick rectangular muscle with superficial and deep components, which originate from the zygomatic arch. The superficial part inserts onto the masseteric tuberosity at the outer surface of the mandibular angle. The deep part runs further dorsally onto the outer part of the mandibular ramus.

This muscle can hypertrophy causing a square-faced appearance. This is usually asymptomatic but can contribute to temporomandubular joint dysfunction and bruxism (teeth-grinding). Toxin will cause atrophy of the muscle, reducing prominence and slimming the jawline.


American Society for Dermatologic Surgery. ASDS survey: nearly 10 million treatments performed in 2015. Available from: https://www. asds.net/_Media.aspx?id=9449. Accessed February 1, 2017.

Botulinum Toxin in Aesthetic Medicine: Myths and Realities

Jeffrey S. Dover, MD, FRCPC,* Gary Monheit, MD,† Mark Greener, BSc(Hons), MRSB,‡ and Andy Pickett, PhDxk

de Sa Earp AP, Marmur ES. The five D’s of botulinum toxin: doses, dilution, diffusion, duration and dogma. J Cosmet Laser Ther 2008;10: 93–102.

Colasante C, Rossetto O, Morbiato L, Pirazzini M, et al. Botulinum neurotoxin type A is internalized and translocated from small synaptic vesicles at the neuromuscular junction. Mol Neurobiol 2013;48:120–7.

Wei J, Xu H, Dong J, Li Q, et al. Prolonging the duration of masseter muscle reduction by adjusting the masticatory movements after the treatment of masseter muscle hypertrophy with botulinum toxin type a injection. Dermatol Surg 2015;41(Suppl 1):S101–9. 

Dr Tristan Mehta

Founder and CEO of Harley Academy

Tristan founded Harley Academy to combat the established lack of standardised medical training provided within the speciality, and works as a cosmetic physician and lead trainer at Harley Academy. He created the nationally recognised Ofqual-regulated Level 7 qualification in Injectables.

Dr Yalda Jamali

Clinical Educational Fellow & Mentor

Dr Jamali combines working with our Courses team to develop teaching content with serving as a lead clinical mentor, notable for her upbeat teaching style. Her successful aesthetics clinic in Nottingham reveals her artistic eye for facial aesthetics.