Increase your intake of vitamin C when you are taking aspirin or some birth control pills as they can lower your vitamin C levels.

You can get vitamin C from citrus fruits (like oranges, lemon, etc), tomatoes, kiwi fruit, sweet potatoes and peppers. Similarly, there are other medications which may lower your other already stored vitamin levels or affect the absorption of supplements. So, ask your doctor if there are any vitamin interactions you should be aware of.