Medi-C Plus Vitamin K2+A+D3 Drops - A convenient combination to maintain immune function, skin, bones, teeth, eyesight and night vision. Supplementing with both vitamin A and D enhances immunity, can help with night vision and preventing macular degeneration. This combination also helps with skin health, and may help with eczema, while high dose vitamin A has been shown to prevent acne. Vitamin K and D work together to increase bone mineral density and bone strength, along with teeth health.