Botox Injections for Patients With Persistent Facial Pain

Inclusion criteria

• Persistent Idiopathic Facial Pain fulfilling diagnostic criteria as classified in The International Classification of Headache Disorders, 3rd edition (ICHD-3 beta version) as modified by the authors of this trial. See below.
• Unsatisfactory effect of available treatment methods as evaluated by a neurologist, ENT specialist or maxillofacial surgeon. The patient should have failed treatment with both anticonvulsant as carbamazepine (Tegretol, Carbatrol) and antidepressant as tricyclic antidepressants
• Average Pain intensity ≥4 (0-10) in Numeric Pain Rating Scale (NRS) on the affected side during the 4-week baseline period
• Written informed consent from the patient

Modified diagnostic criteria for PIFP according to The International

Classification of Headache Disorders, 3rd edition (ICHD-3 beta version):

A. Facial and/or oral pain fulfilling criteria B and C.

B. Recurring daily for >2 hr per day for >3 months

C. Pain has both of the following characteristics:

• Poorly localized and may radiate beyond the trigeminal nerve distribution
• Dull, aching or nagging quality D. Clinical neurological examination is normal, however patient may denote paresthesia E. A dental cause has been excluded by appropriate investigations; signs of structural pathology or other specific causes of pain are not identified. Minor operation and injury (insignificant trauma e.g. tooth extraction) to the face, maxilla, teeth and gums without a direct causal relationship with the pain regarding both time and site is accepted. F. Not better accounted for by another ICHD-3 diagnosis.

Exclusion criteria

• Bilateral symmetrically affected
• Neurological disorders or other related systemic diseases that can explain the pain
• MRI/CT examination confirming intracranial pathology.
• Systemic or local disease or condition that can give a significantly increased risk of complications to the particular procedure
• Not competent to asses informed consent based on neurological assessment
• Psychiatric disorder that prevents the completion of the study
• Pregnancy
• Inappropriate use of contraception
• Breastfeeding
• Abuse or unauthorized use of medication, drugs or alcohol
• Allergy or other hypersensitivity reactions to marcaine, lidocaine, xylocaine, or adrenaline, possibly similar related drugs
• Anatomical factors that prevent or impede the injection
• Known hypersensitivity to botulinum toxin type A or to any of the excipients
• Treatment with drugs that can interact with botulinum toxin type A: aminoglycoside antibiotics, spectinomycin, neuromuscular blockers, both depolarizing (succinylcholine) and non-depolarizing (tubocurarine derivatives), lincosamides, polymyxins, quinidine, magnesium sulfate, anticholinesterases.