Fungi-nail is real medicine. cosmetic nail brighteners that claim a visible difference in just 1 week are not. fungi-nail kills fungus and stops the spread of fungal infections. nail brighteners only temporarily lighten the nail and don't treat the actual toe fungus, allowing it to spread....
Years ago I had nail fungus on my right foot. A dermatologist prescribed a medicine (griseofulvin or some such name) to be applied daily. After a year or two, the fungus was gone except for the great toe. But within a year it was back. Eventually back on all toes on the right foot...