A 7-year-old boy named Timothy, who has asthma, comes to your clinic with his mother. His mother tells you that Timothy has been coughing for a week and has been making a wheezing sound for the last two days. She mentions that they haven't visited the clinic in over a year, and they have run out of Timothy's albuterol inhaler, which he was using three times a day for the past week – his only medication. There is no fever present. Additionally, Timothy's mother reports that he has been complaining of pain in his right ear. Furthermore, you observe dry, scaly patches on Timothy's elbows and behind his knees.

For Timothy's cough, right ear pain and the dry, scaly patches, please provide three potential differential diagnoses (DDx) for each condition, along with your brief reasoning for selecting each DDx. Subsequently, identify the most likely final diagnoses.

Finally, outline a comprehensive plan of care for Timothy's final diagnoses. Include prescription details as if you were sending them to the pharmacy for fulfillment. Explain the patient teaching that should be provided and specify when Timothy should return to the clinic for follow-up. Ensure that your responses are supported by clinical practice guidelines or two high-level scholarly articles. Avoid using point-of-care references.