Hello, Formation of black spots after application of glu cream is not a side effect though there are other side effects like irritation, redness, or swelling. Neither omega-3 nor calcium supplements are typically associated with causing black spots on the skin. Tinea nigra, a rare fungal infection caused by the yeast Hortaea werneckii can causes painless brown or black patches on the palms and sometimes the soles of the feet. If you are experiencing black spots, you are advised to stop using the cream and consult a dermatologist. If it is caused by Tinea nigra and confirmed by dermatologist, you will be treated with a course of oral antifungal medications and given antifungal creams like miconazole to apply locally on the affected area till the infection goes away. A very rare type of skin cancer called melanoma can present as dark spots on the palms. get biopsy done if required so that you can be treated at the earliest. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician