The Glow Supplement Bundle Hair, Skin, Nails & Cellular Wellness
References: Meister A
It can also cause anxiety, along with the low B12

Seek GP advice on the same day if: The injection site becomes increasingly painful, warm, red, or swollensuggesting possible infection (cellulitis) Bruising exceeds 5cm in diameter or continues expanding after 24 hours (as a practical guide) Bruising occurs with every injection despite proper technique New or worsening bruising appears at sites distant from injections Bruising is accompanied by unusual bleeding elsewhere (gums, nose, or gastrointestinal tract) Seek urgent medical attention (call 999) if: Signs of severe allergic reaction develop: facial swelling, breathing difficulty, widespread rash, or dizziness The injection site develops signs of abscess formation: fluctuant swelling, severe pain, or purulent discharge Extensive bruising is accompanied by systemic symptoms: fever, malaise, or unexplained fatigue Sudden onset of multiple bruises without clear trauma, particularly in patients on anticoagulation Patients taking anticoagulant medications should follow their specific monitoring requirements

Handb Exp Pharmacol 233:137171