Final answer:
The observation that would indicate a client is correctly following their medication plan for tricyclic antidepressants is if the client arrives looking neat and appropriate. This improved appearance can be a sign of the positive effects of medication, whereas other listed behaviors may indicate ineffectiveness or side effects of the treatment.
Step-by-step explanation:
An appropriate observation that would indicate a client is following the medication plan correctly while on tricyclic antidepressants would be if the client arrives at the clinic neat and appropriate in appearance (Option C). Improvement in personal grooming and overall appearance can signify a positive response to the treatment. In contrast, not going to work (Option A), stating the inability to 'do anything' (Option B), and excessive sleep (Option D) are not typical indications of effective management with antidepressants and could suggest that the medication regimen needs reevaluation.
It's important to understand that while tricyclic antidepressants may cause some initial side effects such as sleepiness and dizziness, over a period of two to three weeks, they are supposed to help alleviate depressive symptoms in patients. This is in stark contrast to how a non-depressed person might feel upon taking the medication. Treatments for depression vary and may also include psychotherapy, electroconvulsive therapy, deep-brain stimulation, or taking drugs like monoamine oxidase inhibitors or selective serotonin reuptake inhibitors.