Hello,
Dark circles under the eyes are temporary and caused due to insomnia, smoking, a family history of dark circles, deficiency of vitamin K in diet, allergies like sinusitis and eczema, and adrenal gland disorders.
Take rest adequately and eat healthy nutritious food containing lots of green vegetables. Try to avoid caffeine, because it promotes water retention and leads to the dryness of the eye. You should also apply almond oil or skin creams containing vit C or K, alpha hydroxyl acids and kinetin.
I hope that helps. Take care and please do keep us posted in case you have any additional doubts. Kind regards.
I find that drinking lots of water helps. Also get plenty of sleep.