Complex sentence: Although the use of botlinum toxin injections is considered relatively safe, patients' responses to treatment differ in the initial stages; some have reported experiencing swallowing problems and breathy voice quality as a side-effect to the injections.
Split into simpler sentences: Although the use of botlinum toxin injections is considered relatively safe, patients' responses to treatment differ in the initial stages. Some patients have reported experiencing swallowing problems and breathy voice quality as a side-effect to the injections.