Final answer:
Hydroxychloroquine is the drug used to treat skin and arthritic manifestations of Lupus. It is an anti-inflammatory drug that interferes with antigen processing and activation of autoimmunity.
Step-by-step explanation:
The drug used to treat skin and arthritic manifestations of Lupus is Hydroxychloroquine. Hydroxychloroquine is an anti-inflammatory drug that is used to treat inflammation in patients with Lupus, Rheumatoid Arthritis (RA), childhood arthritis, and other autoimmune diseases. It interferes with the processes of antigen processing and activation of autoimmunity. To manage symptoms, it is also advised to limit exposure to sunlight as photosensitivity to sunlight may precipitate rashes.