How can I lighten this dark spot on my nose? It's about the size of a wedding ring (Photo)

Thank you for your question.  Skin discoloration is a very prevalent problem in women over the age of twenty.  It is also increasingly common in men with increased sun exposure.  
Risk factors include thyroid disease, sun exposure, hormones, pregnancy, family history, PIH, and birth control. Melarase AM and Melarase PM have been extremely effective in reducing pigmentation associated with skin discoloration and hyperstimulation of melanocytes. 
In my practice, patients with hyperpigmentation benefit from twice daily application of the creams. Melarase AM in the morning, followed by Melarase PM in the evening. Melarase AM contains four active sunblocks, so sunscreen is not needed unless your sun exposure is very high or you had a recent procedure/laser. SPF of 30. Melarase PM contains active skin lighteners to even out skin pigmentation. If you are concerned about the development of pigmentation, contact our office to discuss details and to obtain a regimen for Melarase. 
Recommendations:  5-step Daily Brightening Kit has everything you need to improve dark spots, skin discoloration, melasma, and hyperpigmentation caused by sun exposure, hormones, scarring, and the environment. It’s a powerful daily brightening kit that can help bring out your skin’s natural, healthy glow. Ideal for use on the face, neck, and hands. 
Includes: Melaclenz, Melapads, Melarase AM, Melarase PM, Elevase, and Spectrase
Best, 
Dr. Karamanoukian
Los Angeles

Either nanosecond q switched laser or picosecond laser can lighten this area. The 1064 wavelength would be safe and effective .There is no downtime. The treat,ent may need to be pressed to get maximum improvement.

Give it time, it will fade. Make sure you use sunscreen as UV can darken the area. New lasers in the picosecond wavelength can help darken spots like these. Picosure using the FOCUS fractional less 6 mm, or older nano 1064 nm laser (Q switch). This is quite a basic treatment, but you will need 3-6 sessions a month apart. Most Board certified plastics or dermatologist can do this treatment in office. All the bestDr Davin Lim Laser DermatologistBRISBANE, Australia