Seek immediate medical attention (call 999 or go to A&E) if you experience: Signs of a severe allergic reaction such as swelling of the face, lips, tongue or throat, difficulty breathing, or severe widespread rash Blood in stools or vomit , which may indicate gastrointestinal bleeding requiring urgent assessment Contact your GP urgently if you experience: Severe or persistent abdominal pain that does not resolve within a few days or worsens over time Persistent vomiting that prevents you from keeping down food, fluids, or medications Severe diarrhoea lasting more than 48 hours, particularly if accompanied by dehydration signs (reduced urination, dizziness, dry mouth) New or worsening symptoms after starting B12 supplementation that significantly impact daily activities or quality of life Routine review is appropriate when: Mild symptoms persist beyond three weeks despite adjusting timing, dose, or formulation You are uncertain whether symptoms relate to B12 supplementation or another condition You have pre-existing gastrointestinal conditions (such as Crohn's disease, coeliac disease, or gastritis) and experience new digestive symptoms You require guidance on alternative supplementation routes, particularly if oral preparations consistently cause discomfort It is important to remember that many gastrointestinal symptoms have multiple potential causes

Who Should NOT Choose Each Avoiding misaligned models is just as important as choosing the right compound
The image below shows a participant at Day 1 and Day 90 (28 days after the third injection)
Developing and testing a new drug is expensive, and companies count on recouping their costs by having, in effect, a monopoly on the market for a new drug
Response: We thank commenters for their support and agree that the removal of the Median Time for Discharged ED Patients and LWBS measures will reduce administrative burden and prevent duplicative reporting
This variability reflects individual biological differences and the research-stage nature of the compound