Introduction: Tension headache is the most common form of headache and has a major socio- economic impact. Chronic tension headache is defined as a headache occurring more than 15 days per month or more than 180 days per year.

It has been argued that tension headache is due to a sustained contraction of the perincranial musculature, although the pathophysiological mechanisms are complex and there is some controversy as to its origin.

Among the treatments described are non-pharmacological (physical exercise, rehabilitation),
pharmacological (analgesics, anti-inflammatory drugs, antidepressants), and botulinum toxin injections.

Botulinum toxin is a neurotoxin that irreversibly blocks the release of acetylcholine from the presynaptic termination of the cholinergic nerve and has demonstrated an analgesic effect in tension headache.

Objective: The aim of the study is to evaluate the effectiveness of botulinum toxin type A infiltration in relieving pain and improving quality of life in patients with tension headache, by means of a prospective quasi-experimental study in the rehabilitation service of the Hospital Dr Negrín, between April 2024 and April 2025, comparing two different doses, 100 and 200 units.

Material and methods: This is a prospective quasi-experimental study in the rehabilitation service of the Hospital Dr Negrín, between April 2024 and April 2025, in which we included 18 patients diagnosed with chronic tension headache, comparing two different doses of toxin, 100 and 200 units respectively, in two groups.

We assessed sex, age, VAS, frequency, concomitant symptoms, medication required and quality of life scale using the HIT - 6 questionnaire and compared results after puncture at 3 and 6 months.

We compared the two groups infiltrating different amounts (100 and 200 U) and number of muscles. In the first group, masseter, splenius and temporalis muscles were infiltrated, and in the second group, occipital, corrugator, splenius and trapezius muscles were added.

The main objective of the study is to check the efficacy of incobotulinum toxin A at 3 months and to assess the time of efficacy if it exists. The secondary objectives are to assess the frequency of onset, accompanying symptoms and quality of life of the patient according to a questionnaire.

Conclusion: The study is pending statistical results.

I am a doctor specialising in rehabilitation, working since 2002 at the Hospital Dr. NEgrín. Specialist in musculoskeletal pathology (I was part of the chronic pain unit for 15 years as part of a multidisciplinary team), in lymphoedema and pelvic floor pathology. She performs interventional rehabilitation once a week.