Authors: Lei Wu, Xingcheng Li, Yangshan Fu, Fenshuang Zheng, Jialong Chen
Categories: Review, Dysphagia, Muscle weakness, Botulinum toxin
Source: Dysphagia
Authors: Lei Wu, Xingcheng Li, Yangshan Fu, Fenshuang Zheng, Jialong Chen
Botulinum toxin (BoNT), a neurotoxic protein produced by Clostridium botulinum, is widely used for cosmetic and therapeutic purposes, including managing muscle hyperactivity, movement disorders, and chronic migraines by blocking acetylcholine release at neuromuscular junctions. While generally safe, it can cause localized adverse effects (erythema, ptosis, pain) and rare systemic complications (dysphagia, dysarthria, respiratory distress), particularly with improper dosing. From August 2024, This case report presents three female patients, aged 25, 50, and 49, in the Affiliated Hospital of Yunnan University, who experienced severe complications following the injection of botulinum toxin. The first patient, developed dysarthria and dysphagia 18 days post-injection, with a history of administration in northern Myanmar. The second patient, reported similar symptoms 3 days after a lesser dosage was injected into her masseter muscles. The third patient, exhibited fatigue and difficulty in eye opening and swallowing 7 days after receiving botulinum toxin. The symptoms of all patients were significantly improved after receiving symptomatic treatment in our hospital. The three cases presented are significant as they highlight the potential complications arising from botulinum toxin injections, particularly when used for cosmetic purposes. Botulinum toxin, though effective for cosmetic and therapeutic applications, carries risks of localized (muscle weakness, ptosis, bone loss) and systemic complications (generalized weakness, botulism), particularly near critical anatomical structures. Dysphagia and dysarthria, observed in cases post-injection, likely arise from toxin diffusion causing unintended muscle impairment. Treatment outcomes vary, with supportive care or invasive interventions often yielding limited improvement, highlighting management challenges. Clinicians must prioritize patient education, informed consent, and vigilant post-treatment monitoring for neurological symptoms. Future guidelines should standardize safe administration practices—optimizing dosage, injection sites, and follow-up—while enhanced practitioner training and multidisciplinary approaches are critical to mitigating risks and improving outcomes. This underscores the imperative for heightened clinical awareness and robust safety protocols to safeguard patient welfare.
Botulinum toxin, a neurotoxic protein produced by the bacterium Clostridium botulinum, is widely used in both cosmetic and therapeutic applications. Botulinum neurotoxins (BoNTs) have multiple medical applications, including treatment of muscle hyperactivity, movement disorders, and pain syndromes like chronic migraine [1].Botulinum toxin A has therapeutic and aesthetic benefits, but serious side effects can occur, such as erythema, oedema, pain, ptosis of eyelid or brow, and ecchymosis [2].Botulinum neurotoxins (BoNTs) have multiple medical applications, including treatment of muscle hyperactivity, movement disorders, and pain syndromes like chronic migrain [1].These suggest that botulinum toxin acts by blocking the release of acetylcholine at the neuromuscular junction, leading to temporary muscle paralysis, while also having additional effects such as reducing neurotransmitter release, modulating pain pathways, and affecting autonomic and sensory neurons [3, 4].
These studies suggest that while botulinum toxin is generally effective and safe for various therapeutic and cosmetic uses, it can cause adverse effects ranging from mild, localized reactions like erythema and ptosis to serious systemic complications such as respiratory distress, muscle weakness, and even death, particularly when used in high doses or improperly [2, 5, 6].
These studies suggest that while botulinum toxin administration is generally safe and effective for both cosmetic and medical purposes, it can lead to mild and transient complications such as pain, swelling, and ptosis, as well as rare but serious adverse effects like systemic spread and muscle weakness, underscoring the importance of careful patient selection, precise injection techniques, and thorough monitoring [2, 7].
In this case report, we present three patients who developed significant complications, including dysarthria and dysphagia. following botulinum toxin injections, These cases are particularly noteworthy as they highlight the potential risks associated with botulinum toxin use, especially in individuals who may not be adequately informed about the possible side effects. These complications are very common, particularly in the context of cosmetic procedures, emphasizes the need for heightened awareness among healthcare providers when considering botulinum toxin injections for patients presenting with symptoms such as speech difficulties and swallowing problems. This report aims to contribute to the existing literature by providing insights into the clinical implications of botulinum toxin-related complications and the importance of differential diagnosis in similar cases.
The patient, a 25-year-old female, was admitted to the hospital due to progressive slurred speech and dysphagia for 18 days on August 20, 2024. On July 28, 2024, the patient received face and shoulder injection of botulinum toxin labeled as “South Korea imported” (total amount of 200U, divided into 2 bottles) in non-medical institutions in Mujie City, Myanmar. On the fourth day after injection (August 1), dizziness developed, and dysarthria, dysphagia, and neck muscle weakness developed the next morning. He was transferred to Ruili Jingcheng Hospital for nutritional support on August 11. On August 19, he was placed with a gastric tube due to dysphagia. There was no fever, disturbance of consciousness or abnormal physical activity during the course of the disease. Physical vital heart rate 119 beats/min (sinus), the rest of the normal. Nervous clear consciousness, dysarthsia (NIHSS score 1), decreased bilateral pharyngeal reflex, cervical flexion muscle strength grade IV, limb muscle strength grade V-, normal and symmetrical muscle tension, normal depth and superficial sensation, and negative pathological signs. Meningeal irritation was negative. Auxiliary one. Neurogenic electromyography changes, peripheral nerve motor fiber axon moderate to severe damage, mainly in the upper limbs; two. Severe neuromuscular junction damage. Treatment and intravenous infusion of botulinum antitoxin 50 000 U, methylprednisolone pulse therapy (500 mg/d×3d), nasal feeding nutritional support and rehabilitation training. On the third day of treatment, swallowing function improved, and the gastric tube was removed on the seventh day. He was discharged after 21 days of hospitalization with complete symptom resolution (Fig. 1).
Fig. 1Notes: (1) Electrophysiological diagnosis of NCS+ sensory disorders of extremities +F decreased amplitude of motor conduction fibers in bilateral median nerves, bilateral ulnar nerves and bilateral common peroneal nerves, decreased occurrence rate of F wave (decreased M wave) in bilateral median nerves, and no obvious abnormalities were found in other nerves. (2) Repetitive electrical (1) Low frequency the ulnar nerve amplitude decreased by 10.8%, and the accessory nerve amplitude decreased by 16.7%; (2) High frequency the amplitude of ulnar nerve increased. 3. EMG: a small amount of spontaneous potentials were observed in the examined muscles. The waveforms of the muscles with light contraction were poorly differentiated, and no obvious abnormalities were observed in the muscles with strong recruitment
A 50-year-old female patient was admitted to the hospital due to progressive dysarthria with dysphagia for 3 days on August 19, 2024. On August 12, 2024, the patient received bilateral masseter injection labeled “South Korea imported botulinum toxin” (100U), and bilateral periocular injection in non-medical institutions. On the 4th day after operation, he developed slurred speech, choking and weakness of limbs, and the symptoms continued to progress during the treatment in Baoshan People’s Hospital. Physical Vital heart rate 112 beats/min (sinus), rest normal. Nervous conscious, dysarthsia (NIHSS score 2), bilateral soft palate weakness, pharyngeal reflex loss, bilateral orbicularis oculi muscle strength grade IV, masseter muscle strength grade III, proximal limb muscle strength grade IV, distal limb muscle strength grade V-, deep and shallow sensory symmetry, bilateral Hoffmann sign negative.
Auxiliary Neurogenic electromyography changes, peripheral nerve motor fiber axonal mild to moderate damage, mainly in the upper limbs; Moderate neuromuscular junction damage. Treatment and After the diagnosis was established, botulinum antitoxin 100 000 IU intravenous infusion, methylprednisolone 500 mg/d pulse therapy, swallowing rehabilitation training and nutritional support were started. After 17 days of hospitalization, the symptoms were significantly relieved and the patient was discharged (Fig. 2).
Fig. 2Notes: (1) Electrophysiological diagnosis of NCS+ sensory disorders of extremities +F decreased amplitude of motor conduction fibers in bilateral median nerve and bilateral ulnar nerve, decreased F-wave elicited rate in left median nerve, and no obvious abnormalities were found in other nerves. 2. Repetitive electrical (1) Low frequency the ulnar nerve amplitude decreased by 8%, and the accessory nerve amplitude decreased by 26.4%; (2) High frequency the amplitude of ulnar nerve increased. 3. EMG: there were no obvious abnormalities in spontaneous potential, light contraction and vigorous recruitment of muscles
A 49-year-old female patient was admitted to the hospital due to “progressive ptosis with dysphagia for 7 days” on August 7, 2024. On behalf of the patient’s family, the patient received bilateral masseter muscle injection of “botulinum toxin six-peptide lyophilized powder” (unknown dose) at a non-medical institution on August 2, and pain at the injection site occurred on the day after surgery. On August 5, a sudden onset of ptosis, dysphagia, and generalized myalgia occurred. The patient was transferred to our hospital after ineffective treatment in other hospitals. Physical Vital body temperature 37.8℃, heart rate 108 beats/min. Nervous bilateral ptosis (right eye fissure 3 mm/ left eye fissure 4 mm), pupil hypersensitivity to light reflex, normal bilateral eye movements in all directions, dysarthria (NIHSS score 3). Muscle strength of the extremities was grade III proximal and grade IV distal. Auxiliary Nerve conduction Neurogenic electromyography changes, peripheral nerve motor fiber axonal moderate to severe damage; Severe neuromuscular junction damage. Treatment and botulinum antitoxin 100 000 IU intravenous infusion, methylprednisolone 500 mg/d pulse therapy, rehabilitation training and nutritional support. After 29 days of hospitalization, the symptoms were significantly relieved and the patient was discharged (Fig. 3).
Fig. 3Notes: 1.Electrophysiological diagnosis of NCS+ sensory disorders of extremities +F decreased amplitude of motor conduction fibers in bilateral median nerves, bilateral ulnar nerves and left common peroneal nerves, decreased F-wave elicited rate in bilateral median nerves, bilateral ulnar nerves and bilateral tibial nerves, and no obvious abnormalities were found in other nerves. 2. Repetitive electrical (1) Low-frequency the amplitude of ulnar nerve decreased by 6.5%, and the amplitude of accessory nerve decreased by 21.2%; (2) High frequency the amplitude of ulnar nerve increased. 3. Electromyography (EMG): the spontaneous potential, light contraction and vigorous recruitment of the examined muscles were normal
The three cases presented are significant as they highlight the potential complications arising from botulinum toxin injections, particularly when used for cosmetic purposes. The patients exhibited common symptoms of dysarthria and dysphagia after receiving injections, which raises important questions about the safety and monitoring of such interventions, especially in young adults and middle-aged individuals. Given the increasing popularity of botulinum toxin for aesthetic treatments, understanding the adverse outcomes associated with its use is vital for both clinicians and patients.
Current literature indicates that botulinum toxin, while effective for its intended applications, can lead to unintended side effects such as local muscle weakness, ptosis, bone loss, and rare systemic effects like generalized weakness and botulism, particularly when injected near critical anatomical structures [8–10].Reports have documented cases of dysphagia and dysarthria following injections, which may be attributed to the diffusion of the toxin beyond the intended site of action, resulting in muscle weakness and impairments in motor function [11, 12]. The symptoms observed in our patients align with these findings, indicating that careful consideration and thorough assessment of patient histories are essential prior to administration.
The treatment processes for the patients varied across institutions, with some receiving supportive care such as fluid resuscitation and nutritional support, while others had more invasive interventions, such as the placement of feeding tubes. The lack of significant improvement in symptoms despite these interventions underscores the challenges associated with managing botulinum toxin-related complications. It is crucial for healthcare providers to be aware of these risks and the potential need for multidisciplinary approaches in the treatment of affected individuals.
These cases emphasize the necessity for clinicians to educate patients about the risks linked to botulinum toxin injections, ensuring informed consent is obtained before procedures. Furthermore, increased vigilance in monitoring for neurological symptoms following treatment is imperative. Future clinical practice should incorporate guidelines for the safe administration of botulinum toxin, including recommendations for dosage, injection sites, and patient follow-up [13, 14]. Enhanced training for practitioners performing these procedures could potentially mitigate the risk of adverse effects and improve patient outcomes in the aesthetic and therapeutic use of botulinum toxin.
Clinicians must prioritize patient education, informed consent, and vigilant post-treatment monitoring for neurological symptoms. Future guidelines should standardize safe administration practices—optimizing dosage, injection sites, and follow-up—while enhanced practitioner training and multidisciplinary approaches are critical to mitigating risks and improving outcomes. This underscores the imperative for heightened clinical awareness and robust safety protocols to safeguard patient welfare.