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What Are the Possible Complications after Botox injection?

Botulinum toxin injection is considered safe though there are rare cases f complications. This article explains the complications after Botulinum toxin injection, such as brow ptosis, asymmetry and lip ptosis, injection site complications, and frequently asked questions.

Most clients have been choosing injectable treatments like botulinum toxin and fillers to rejuvenate and eliminate facial wrinkles. These procedures are considered safe, although certain complications can accompany them. Botulinum toxin injection has its difficulties like any other medication. The side effects are not permanent; they last for a few hours or days. Complications are, however, serious and may require immediate medical attention; patients are advised to take immediate action and see a cosmetic doctor. Complications from botulinum injections include;

Brow Ptosis

According to Yi et al. (2022), brow ptosis is a frequent side effect that might occur while using anti-wrinkles injections to treat the frontalis muscle and reduce forehead lines and wrinkles. It is a plunge of an eyebrow from its natural position to a point where it is aesthetically unappealing, or deficiencies happen due to other soft tissues pressing down on the eyelid. This condition is commonly observed in elderly clients due to the variation of facial face tissues. This complication can be prevented by keeping a distance overhead the supraorbital margin during the frontalis injection. This method preserves the frontalis muscle’s purpose in the region, averting ptosis. There are clients whose horizontal forehead lines are together with glabellar frown lines. The glabellar part should be addressed together with the forehead. Unchallenged depressor nerve action of the glabellar muscles will result in brow ptosis. Injection of large dosages of antiwrinkle injections into the lateral canthus region results in complications like lagophthalmos, xerophthalmia, diplopia, and ectropion (Kassir et al.,2020)Lagophthalmos is an uncommon complication resulting from improper eyelids closing and lack of normal functioning of the orbicularis. All these complications can be minimized by getting an injection from a certified cosmetic practitioner.

Asymmetry and Lip Ptosis

This is another uncommon complication that occurs whenever the toxin is injected along the nasal sidewalls or underneath the superior edge of the zygomatic arch. Overdose of the poison on the upper lip may result in numerous opposing functional variations like difficulty pronouncing some words, different eloquent sounds, and forming some letters; this results in ptosis and lip asymmetry and causes challenges when eating or speaking (Yi et al., 2022). Difficulties sealing the lips may result in fluid or drooling and food incontinence.

Hoarseness, Dysphagia, and Neck Weakness

Anti-wrinkle injections of vertical bands and horizontal rhytides in the neck are considered safe though complications may arise due to an improper method. A deeper injection or a large amount of botulinum toxin doses leads to neck weaknesses, dysarthria, dysphagia, and xerostomia (Yi et al. (2022). Some clients may report difficulty in lifting the head and keeping it erect and still. When clients notice this complication, they should immediately consult a cosmetic doctor.

Injection Site Complication

Some patients experience severe headaches. These complications include pain, bruising, erythema, and edema at the injection site. When cosmetic doctors utilize a small syringe and pay attention to the blood vessels, they can limit bruising, particularly in the lateral canthus area. Arnica, vitamin K and aloe vera are creams that patients can use to reduce bruising and swelling. Some serious reactions, such as dyspnea, edema, and soft tissues, are rare.

Urinary Retention

According to Schaake et al. (2018), urinary retention has symptoms like burning sensations when urinating, distress, and frequent urinating, a potential complication of Botulinum toxin injection. With these complications, patients can experience difficulties in emptying their bladders. Also, the complication affects patients who use Botulinum toxin injection in treating urinary incontinence and overactive bladder. Clients should take immediate action when they observe this symptom and see a cosmetic doctor.

Upper Respiratory Tract Infection

The upper respiratory tract infection manifest through sneezing, sore and scratchy throat, runny nose, pressure behind the face, and cough. The respiratory complication is common for patients who take Botulinum toxin injections to treat spasticity and cervical dystonia. If patients experience any symptoms of this infection, they should consult a cosmetic doctor as early as possible. 

Spread of Toxin Effects

Botulinum toxin injection comes with a boxed warning; the boxed warning targets the patients and the cosmetic doctors about harmful side effects of the antiwrinkle injection. Botulinum toxin injection diffuses from the treated area to other parts of the body, and it is called botulism. Botulism happens after infection for hours, days, weeks, and even months. The symptoms include muscle weakness, loss of control over the bladder, hoarse voice, double vision, drooping eyelids, trouble swallowing, speaking, breathing, and fatigue. Patients who experience swallowing or breathing symptoms after the injection should consult a cosmetic doctor.

Allergic Reactions

In some patients, Botulinum toxin injection may trigger allergic reactions. Symptoms include tongue, mouth, or throat, swelling under the skin, especially in the hands, feet, eyelids, and lips, flushing, itching, and rash. When clients observe these symptoms, they should consult a cosmetic doctor.

Frequently Asked Questions about Botulinum toxin injection

When Do Botulinum Toxin Injection Effects Go Away?

Generally, side effects go away after a few days post-treatment. However, the side effects vary from client to client. The duration of the side effects depends on the condition of using Botulinum toxin injection. When the side effects become severe, patients should seek medical advice as soon as possible.

Can Botulinum Toxin Injection Cause Any Brain Side Effects?

There are no reports that Botulinum toxin injection affects the brain. 

What Are The Most Common Side Effects of Botulinum toxin injection? 

The common side effects include drooping eyelids, redness or pain at the injection site, muscle weakness, muscle stiffness, and neck pain. 

Why Do I Feel Sick after Botulinum toxin injection? 

After the injection, clients may experience pain, infection, bruising, and redness. They may also experience trouble swallowing, dizziness, respiratory diseases like headache, nausea, pain, flu or cold, and muscle weakness. 


Botulinum toxin injection is considered a safe injectable method. However, there may be complications after the treatment. Some may disappear independently, while others may need medical attention. Clients should take immediate action to prevent serious implications when they observe any difficulty. After the injection, patients can experience swelling, bleeding, bruising, and redness. Notably, the botulinum toxin injections are irreversible; the patient must wait 6 months to correct anomalies with the treatment. Therefore, one should take treatment from a certified practitioner to prevent complications.


Kassir, M., Gupta, M., Galadari, H., Kroumpouzos, G., Katsambas, A., Lotti, T., … &Goldust, M. (2020). Complications of botulinum toxin and fillers: A narrative review. Journal of cosmetic dermatology, 19(3), 570-573.

Papageorgiou, E., Lazari, K., &Gottlob, I. (2021). The challenges faced by clinicians diagnosing and treating infantile nystagmus Part II: treatment. Expert Review of Ophthalmology, 16(6), 449-465.

Schaake, W., van der Schaaf, A., van Dijk, L. V., van den Bergh, A. C., &Langendijk, J. A. (2018). Development of a prediction model for late urinary incontinence, hematuria, pain and voiding frequency among irradiated prostate cancer patients. PLoS One, 13(7), e0197757.

Yi, K. H., Lee, J. H., Hu, H. W., & Kim, H. J. (2022). Anatomical Proposal for Botulinum Neurotoxin Injection for Glabellar Frown Lines. Toxins, 14(4), 268.

Ksenia Sobchak