Flexeril or cyclobenzaprine or baclofen are not associated with hoarseness
of voice. More plausible causes of hoarseness
of voice need to be checked like acute laryngitis, vocal cord nodules, allergies, gastro esophageal reflux, smoking, thyroid problems, trauma to larynx, parkinson’s disease and trauma to larynx. Consult an otolaryngologist who will evaluate the causes and treat likewise. Cough suppressants for laryngitis, treat GERD, stop smoking, vocal rest etc will make a difference.