{
  "what": "Botulinum toxin (BTX) is a prescription medicine that blocks the release of acetylcholine at the nerve ending, so a chosen muscle contracts less and the line it makes softens. At Dr Sin Yong's practice on Orchard Road, Singapore, it is used in two categories: relaxing the muscles behind dynamic lines such as frown lines, forehead lines and crow's feet, and reducing muscle bulk for contouring. He examines each muscle in movement and sets the dose himself; lines already etched at rest need skin remodelling or filler instead.",
  "key_facts": [
    "Areas: frown lines (corrugator and procerus), forehead lines (frontalis), crow's feet (outer orbicularis oculi), bunny lines (nasalis), the depressor anguli oris, platysmal neck bands, the masseter for jaw slimming, the trapezius and calf, and underarm sweating, where it acts on the nerve signal to sweat glands",
    "Dose mapping: the muscle is examined at rest and in movement; brow position and lid reserve are read before the forehead is relaxed; asymmetry is dosed side by side; dosing starts conservatively and is reviewed at a follow-up timed individually",
    "Units: potency units are specific to each formulation's own assay and cannot be converted between brands, so any product used elsewhere is recorded before a dose is set",
    "Does not: add volume, tighten loose skin or remove lines fixed at rest; it is not a filler",
    "Should not have: pregnancy or breastfeeding, a neuromuscular disorder such as myasthenia gravis, allergy to a botulinum toxin product, active infection at the sites, or unreviewed blood-thinning or neuromuscular-acting medicines; droopy lids from muscle or heavy skin are referred to an oculoplastic or plastic surgery specialist",
    "Risks: small bruises, tenderness and mild headache; less commonly asymmetry, a heavy brow or eyelid, a changed smile or tiredness when chewing, which last as long as the toxin and cannot be reversed on demand; rarely widespread weakness or difficulty swallowing or breathing, which needs urgent care",
    "Duration: the effect is temporary and fades at a pace that differs between people and with the dose; muscle activity returns, so treatment can be stopped at any time, and no duration is promised",
    "Performed by: Dr Sin Yong personally, who assesses and injects each treatment"
  ],
  "references": [
    "Peer-reviewed pharmacology literature on formulation-specific dosing units. Toxins 2024. https://doi.org/10.3390/toxins16060266",
    "Carruthers J, Fagien S, Matarasso SL. Consensus recommendations on the use of botulinum toxin type A in facial aesthetics. Plastic and Reconstructive Surgery 2004. https://pubmed.ncbi.nlm.nih.gov/15507786/",
    "Prescribing information for onabotulinumtoxinA for injection (cosmetic), including the glabellar lines indication. US Food and Drug Administration 2018. https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/103000s5306lbl.pdf",
    "Infosearch: public registers of therapeutic products and medical devices in Singapore. Health Sciences Authority 2026. https://www.hsa.gov.sg/e-services/infosearch/",
    "Efficacy and Safety of Botulinum Toxin Type A in the Treatment of Glabellar Lines: A Meta-Analysis of Randomized, Placebo-Controlled, Double-Blind Trials. Plastic and Reconstructive Surgery 2015. https://pubmed.ncbi.nlm.nih.gov/26313835/",
    "Meta-Analysis of Adverse Reactions of Botulinum Toxin A in Facial Rejuvenation Treatment. Aesthetic Plastic Surgery 2025. https://pubmed.ncbi.nlm.nih.gov/39623228/",
    "Consensus Recommendations for Combined Aesthetic Interventions Using Botulinum Toxin, Fillers, and Energy-Based Devices. Dermatologic Surgery. https://pubmed.ncbi.nlm.nih.gov/27100962/"
  ],
  "owner_url": "https://drsinyong.com/wrinkles-prevention-btx/",
  "doctor": "Dr Sin Yong, aesthetic physician, Orchard Road, Singapore",
  "updated": "2026-10-31"
}