Sub-therapeutic use of botulinum toxin in cervical dystonia, blepharospasm, hemifacialspasm and post herpetic neuralgia during pregnancy : A prospective study

Abstract

We aimed to study sub therapeutic (to reduce intensity of discomfort) and safe dose administration of BoTn/A in certain dystonic neurological movement disorders and Post herpetic Neuralgia (PHN) during pregnancy. Total 7 cases studied [(Cervical dystonia =1), (Blepharospasm =2), (Hemi facial spasm=1) and (PHN=3)].BoTn/A (dysport – SPEYWOOD) was diluted in 10 ml of normal saline. Arbitrary 200 to 500 units was administerd depending upon clinical assessment. The patients followed at 1, 3, 4, 12 and 16 weeks. The fetal well being was assessed after delivery and maximum follow-up to 1 and half year period.Botulinum toxin type a is used as a therapeutic agent in various hyper active movement disorders such as cervical dystonia, blepharospasm, hemi facial spasm and intractable neuropathic pain such as post herpetic neuralgia (PHN). It is an exotoxin produced by clostridium botulinum. It prevents the release of acetylcholine thereby preventing the muscle contraction and reducing pain transmission. The mean age was 35 years. The severity of spasm assessed on intensity, range and frequency of contraction of muscles. In PHN pain intensity measured on VAS score. There was a significant subjective improvement in the spasm in cervical dystonia, blepharo spasm, & hemifacial spasm. The VAS score reduced significantly in all three cases. The fetuses born were healthy and no congenital malformation observed. The children were followed by an average one year were found healthy. We observed that BoTn/A decreased subjective discomfort in Dystonia, spasm and in the intensity of neuropathic pain. It is safer to administer during pregnancy particularly in third trimester as the fetus born were healthy. The oral medications such as antiepileptic are not without side effects. Therefore, we conclude that it is safer to administer during pregnancy particularly in third trimester. However, larger study is needed.