Yes, only if you are actually allergic to collagen. It is possible to be allergic to collagen.
No, it is not possible to be allergic to blood. Your immune system violently reacts to the allergens you are allergic to. If anyone were allergic to blood, they'd be dead by now. But it is possible to have a phobia of blood.
Yes
yes. i am allergic to the metal in the needles but the doctor does not know why.
Controlling humidity in one's home is an important way to prevent problems like skin irritation, allergic reactions and damaged walls or floors. Humidity can be lowered with vents, opened windows, and dehumidifiers. If the humidity is too low, it can be raised by using a humidifier.
Yes
Yes
no, are you crazy?
yes, it is possible to be allergic to anything.
Yes it is i have a friend who is allergic reaction to limestone dust
No, it is not possible to be allergic to the 'menstrual hormones'. If you are female then those hormones are present throughout your menstrual cycle so if you were allergic you'd see symptoms at all times. These are natural hormones and part of your body, you can't be allergic to yourself.
It is possible to be allergic to almost any substance. Only a doctor can tell you for sure, through proper testing.