Botulinum Toxin — Hyperhidrosis (Excessive Sweating)

Botulinum toxin injections into the sweat glands of the underarms (axillae) to treat primary hyperhidrosis — excessive sweating that persists regardless of temperature or physical activity. By blocking the acetylcholine signals that trigger eccrine sweat-gland secretion, the treatment dramatically reduces sweating in the treated area for seven to twelve months, far longer than the effect seen in facial muscle applications. At Estetické centrum Praha MUDr. Handlová performs a contact starch-iodine test before the procedure to precisely locate the most active sweat-gland zones, ensuring targeted injection placement.

Primary hyperhidrosis is a condition characterised by excessive sweating beyond what the body needs for thermoregulation, typically affecting the axillae, palms or forehead. When conservative treatments such as prescription antiperspirants fail to provide adequate control, botulinum toxin injection into the eccrine sweat glands is one of the most effective and evidence-backed interventions available without surgery. The mechanism differs from the facial muscle application: rather than blocking a neuromuscular junction, the toxin here inhibits the cholinergic sympathetic nerve fibres that innervate the eccrine glands. Without the acetylcholine signal, the gland cells cannot be stimulated to secrete sweat. Because sweat glands are not muscle fibres and do not regenerate their receptor apparatus as quickly, the duration of effect in hyperhidrosis is considerably longer — seven to twelve months is typical for axillary treatment, compared to three to four months for facial muscles. At Estetické centrum Praha MUDr. Renata Handlová begins the procedure with a contact starch-iodine test: the underarm is dried, painted with iodine solution and then dusted with starch. Where sweat is actively produced, the iodine-starch combination turns a characteristic dark blue-black, generating a map of the most active secreting zones. This map guides the injection grid, ensuring that the botulinum toxin is deposited at each active gland cluster rather than distributed uniformly — improving efficacy and reducing the total dose required. The injections themselves are delivered with fine needles into the skin of the axilla at each marked point. The procedure takes fifteen to thirty minutes per axilla. Patients can return to normal activities the same day; underarm massage and pressure should be avoided for the first few hours. Onset of the drying effect is typically observed within five to seven days, with full suppression by day fourteen. When sweating begins to return as the effect wanes, the treatment can be safely repeated. The same approach can be applied to palmar (palm) hyperhidrosis, which may require topical anaesthetic or nerve block before injection due to the higher sensitivity of palmar skin. Plantar (foot) hyperhidrosis can also be treated. Contraindications include pregnancy, breastfeeding, active neuromuscular disease and concurrent aminoglycoside antibiotic use.