Selective Mutism

Selective mutism is consistent failure to speak in specific social situations (typically school) despite speaking in others, lasting at least one month.

• Prevalence 0.5 to 1%, onset before 5 years, usually recognised at school entry; a social anxiety variant in most.
• Risk factors: behavioural inhibition, family anxiety, bilingualism or language disorder, speech delay.
• Comorbid social anxiety, separation anxiety, language and developmental disorders.
• Without treatment may persist into adolescence.

• Silence or whispering at school or in public, normal speech at home; nonverbal communication (nodding, pointing).
• Freezing, stiff posture, avoidance of eye contact, shyness.
• Academic assessment hampered; social isolation and bullying.

• Clinical, with parent and teacher reports and Selective Mutism Questionnaire; home videos of speech.
• Hearing test, speech and language assessment, developmental assessment for autism and intellectual disability.
• Exclude communication disorders, trauma, psychosis, elective mutism due to language unfamiliarity.

• Behavioural therapy: stimulus fading, shaping, graded exposure, positive reinforcement delivered with teachers and parents, first line.
• Psychoeducation for school staff; avoid pressure to speak.
• SSRI for moderate to severe or nonresponse: fluoxetine 10 to 60 mg daily or sertraline 25 to 150 mg daily, with monitoring for activation.
• Speech and language therapy for comorbid disorders.
• Treat parental anxiety; review progress each term.