Hi. Forgetfulness at the age of 55 can be suggestive of dementia. However, the other symptoms of irritability, decreased sleep, tiredness also seem to point towards depression. Forgetfulness can also be part of depression as well. Please consult a psychiatrist and get your father evaluated completely. Treatment accordingly can be initiated.
Next Steps
Seek a psychiatric consultation.
Health Tips
Make sure his blood
sugar levels and blood pressure remains under control and is monitored regularly.