I Googled Vitamin D Injections and found several articles on the subject. Like the article I included below says you want to avoid D2. Vitamin D3 is what you want/need to take. Did your doctor check your levels of Vitamin D via a blood test? He can recommend what dosage to take. I take 5,000 IU's of D3 per day. It's a very inexpensive supplement.

"People 50 to 70 years old should get 10 mcg daily (400 IU), and those over 70 should get 15 mcg daily (600 IU). Based on recent research, Dr. Weil recommends 2,000 IU of vitamin D per
day. Look for supplements that provide D3 (cholecalciferol) rather than D2 (ergocalciferol)."

Vitamin D | Vitamin D Supplements | Andrew Weil, M.D.


"Vitamin D Injections- despite what your doctor may tell you- are really just NEVER necessary. They are INFERIOR in every way to oral Vitamin D Supplements and sunlight because of the fact that they are, without exception, Vitamin D2. And I will repeat this, YOU DO NOT WANT TO TAKE VITAMIN D2."

Vitamin D Injections are Unnecessary and Painful