A​ ​9-month-old​ ​male​ ​intact​ ​Labrador​ ​mix​ ​was​ ​presented​ ​to​ ​the​ ​Cornell​ ​University Hospital​ ​for​ ​Animals​ ​(CUHA)​ ​Internal​ ​Medicine​ ​Service​ ​on​ ​August​ ​15,​ ​2017,​ ​with​ ​a​ ​history​ ​of regurgitation​ ​and​ ​weight​ ​loss.​ ​The​ ​owners​ ​reported​ ​the​ ​patient​ ​regurgitating​ ​some​ ​food​ ​or​ ​water shortly​ ​after​ ​every​ ​meal​ ​since​ ​they​ ​adopted​ ​him​ ​at​ ​9-weeks​ ​of​ ​age.​ ​He​ ​had​ ​been​ ​slowly​ ​losing weight​ ​over​ ​the​ ​preceding​ ​few​ ​months​ ​despite​ ​being​ ​a​ ​young,​ ​active,​ ​growing​ ​puppy.​ ​The primary​ ​veterinarian​ ​took​ ​thoracic​ ​radiographs​ ​and​ ​saw​ ​a​ ​large​ ​diverticulum​ ​in​ ​the​ ​esophagus cranial​ ​to​ ​the​ ​heart​ ​and​ ​a​ ​dilated​ ​esophagus​ ​throughout​ ​the​ ​thoracic​ ​cavity.​ ​He​ ​diagnosed megaesophagus,​ ​with​ ​the​ ​primary​ ​differential​ ​diagnoses​ ​being​ ​congenital​ ​idiopathic megaesophagus​ ​or​ ​secondary​ ​to​ ​a​ ​persistent​ ​right​ ​aortic​ ​arch. The​ ​owners​ ​were​ ​advised​ ​to​ ​feed​ ​him​ ​a​ ​slurry​ ​in​ ​an​ ​elevated​ ​position​ ​and​ ​they​ ​attempted to​ ​keep​ ​him​ ​upright​ ​after​ ​meals​ ​for​ ​5-6​ ​minutes​ ​by​ ​holding​ ​treats​ ​up​ ​for​ ​him​ ​in​ ​a​ ​chair.​ ​They reported​ ​this​ ​seemed​ ​to​ ​delay​ ​regurgitation​ ​for​ ​up​ ​to​ ​an​ ​hour.​ ​However,​ ​he​ ​was​ ​not​ ​monitored closely​ ​throughout​ ​the​ ​day​ ​and​ ​the​ ​owners​ ​suspected​ ​he​ ​often​ ​got​ ​into​ ​things​ ​off​ ​the​ ​counter​ ​and outside​ ​in​ ​the​ ​woods​ ​while​ ​they​ ​were​ ​gone.​ ​The​ ​owners​ ​opted​ ​to​ ​bring​ ​the​ ​patient​ ​to​ ​Cornell’s Internal​ ​Medicine​ ​Service​ ​to​ ​assess​ ​his​ ​eligibility​ ​for​ ​surgery​ ​to​ ​correct​ ​the​ ​megaesophagus. At​ ​Cornell,​ ​the​ ​patient’s​ ​condition​ ​was​ ​discussed​ ​at​ ​length​ ​with​ ​the​ ​owners,​ ​starting​ ​by acknowledging​ ​the​ ​effort​ ​they​ ​were​ ​making​ ​to​ ​keep​ ​him​ ​upright​ ​during​ ​and​ ​after​ ​meals,​ ​and experimenting​ ​to​ ​find​ ​a​ ​consistency​ ​of​ ​kibble​ ​that​ ​worked​ ​best​ ​for​ ​him.​ ​They​ ​were​ ​informed​ ​that there​ ​is​ ​not​ ​a​ ​surgery​ ​to​ ​correct​ ​megaesophagus​ ​and​ ​that​ ​a​ ​persistent​ ​right​ ​aortic​ ​arch​ ​was unlikely​ ​based​ ​on​ ​radiographic​ ​examination,​ ​because​ ​no​ ​narrowing​ ​of​ ​the​ ​esophagus​ ​was​ ​seen. We​ ​offered​ ​them​ ​additional​ ​diagnostics​ ​to​ ​rule​ ​out​ ​some​ ​acquired​ ​causes​ ​of​ ​megaesophagus (namely​ ​blood​ ​tests​ ​for​ ​lead​ ​poisoning,​ ​hypoadrenocorticism​ ​[baseline​ ​cortisol],​ ​hypothyroidism, and​ ​acquired​ ​myasthenia​ ​gravis​ ​[antibodies​ ​to​ ​acetylcholine​ ​receptors]),​ ​but​ ​they​ ​declined​ ​further testing​ ​and​ ​needed​ ​time​ ​to​ ​determine​ ​how​ ​to​ ​proceed. Treatment​ ​options​ ​for​ ​megaesophagus​ ​are​ ​limited​ ​and​ ​most​ ​approaches​ ​focus​ ​on management​ ​through​ ​small,​ ​frequent,​ ​elevated​ ​feedings​ ​and​ ​regular​ ​monitoring​ ​for​ ​signs​ ​of aspiration​ ​pneumonia.​ ​Options​ ​for​ ​tube​ ​feeding​ ​or​ ​surgically​ ​placed​ ​gastrostomy​ ​tubes​ ​may​ ​make it​ ​possible​ ​for​ ​patients​ ​to​ ​regain​ ​and​ ​maintain​ ​weight,​ ​but​ ​they​ ​do​ ​not​ ​address​ ​the​ ​issues​ ​of aspirating​ ​the​ ​dog’s​ ​own​ ​saliva.​ ​There​ ​is​ ​some​ ​evidence​ ​that​ ​sildenafil,​ ​a​ ​potent​ ​vasodilator,​ ​may be​ ​an​ ​effective​ ​pharmacological​ ​treatment​ ​to​ ​reduce​ ​instances​ ​of​ ​regurgitation​ ​and​ ​increase weight​ ​gain​ ​in​ ​dogs​ ​with​ ​congenital​ ​idiopathic​ ​megaesophagus.