So, what happens if you take an expired B12 injection

Testosterone Replacement Therapy: Nausea or vomiting Infertility or decreased sperm count Testicular shrinkage Worsening of obstructive sleep apnea Increase in cholesterol levels Abnormal spike in blood sugar levels, which can increase the risk of developing Type 2 diabetes Yellowing of the skin or around your eyes Uncomfortable swelling or enlargement of breast tissue (gynecomastia) Redness, warmth around lower leg area Unusual increase in red blood cell count, which can result in high blood pressure, joint/muscle pain, trouble with eyesight or thrombosis (blood clotting) Frequent need to urinate Fluid retention Acne or oily skin Headaches Lumps or hardening around injection site Clomid: Headaches Nausea Bloating Mood swings Diminished sex drive Sperm counts decrease (can be reversed by changing Clomid to another type of estrogen blocker, such as tamoxifen.) Acne Chest tenderness Blurry vision Weight gain High blood pressure (hypertension) Altered taste Asthma Flushing Excess thirst Joint aches Enclomiphene Libido issues Acne A temper if levels get too high Mood swings Depression Mood irritability Anxiety Gynecomastia Headache Nausea Diarrhea Dizziness Common Cold Hot flush Joint pain NOTE: Enclomiphene is the purified isomer of Clomid (Clomiphene Citrate)

So, B12 injections can last for one month with slow release into the blood. In contrast, an IV (intravenous) infusion gives you the dose immediately so that you get the benefits immediately, and the effects are shorter lived
Regular B12 shots can play a huge part in improving your mood
For a deeper dive into how it works, you can check out our guide on how to test for B12 deficiency at home
Once the needle is in place, gently pull back on the plunger just a tiny bit