Always Tired? It Could Be B12 Deficiency

Do You Have B12 Deficiency?

Fatigue that does not shift, no matter how much sleep you get, is a sign something is wrong. One common culprit is vitamin B12 deficiency. Your body needs B12 to make red blood cells and keep your nervous system working properly. Without enough of it, you feel exhausted, foggy, and sometimes weak.

The tricky part is that B12 deficiency can hide. You might blame stress, age, or a busy life. But if the tiredness is new, persistent, or comes with other symptoms, it is worth investigating.

Who Needs to Worry About B12?

B12 deficiency is not rare. It affects around 1 in 25 people in the UK, though the figure is higher in older adults. Some people are at greater risk than others.

You are more likely to be deficient if you are over 50, because your stomach produces less of the acid needed to release B12 from food. Vegans and vegetarians are at higher risk because B12 is found mainly in animal products. People taking metformin for diabetes, or long-term proton pump inhibitors for reflux, are also vulnerable. If you have had stomach surgery, your body may not absorb B12 well. Coeliac disease and Crohn's disease can also interfere with absorption.

If any of these apply to you, or if you have felt persistently tired for weeks, it is worth asking your GP for a blood test.

The Main Options

Get a Blood Test First

Before you do anything else, you need to know if you actually have B12 deficiency. Your GP can order a blood test that measures your B12 level. This is free on the NHS. It usually takes a week or two for results.

If your level is low, your GP may do a second test to check your folate level, because folate deficiency can cause similar symptoms. They may also check for pernicious anaemia, an autoimmune condition that prevents B12 absorption.

This step matters because treating B12 deficiency when you do not have it will not help, and there are other causes of fatigue worth ruling out.

B12 Injections

If your test confirms deficiency, B12 injections are the most effective treatment. The injection bypasses your digestive system and delivers B12 straight into your bloodstream, so your body absorbs it fully.

Most people feel better within days or weeks. Energy returns, brain fog lifts, and sometimes mood improves too. The injections are quick, usually given into a muscle in your arm or thigh. They are safe, with very few side effects.

How often you need them depends on the cause of your deficiency. If you have pernicious anaemia, you will likely need injections every 8 to 12 weeks for life. If your deficiency is due to diet or medication, you might need a course of injections followed by oral tablets or dietary changes.

South Ealing Pharmacy offers B12 injections by appointment. Your pharmacist will discuss how often you need them based on your situation.

Oral Tablets or Supplements

If your deficiency is mild or caused by diet, your GP might suggest high-dose oral B12 tablets instead of injections. These work, but less reliably than injections, because absorption through the gut is unpredictable.

Oral supplements are useful for maintenance once your levels are restored, or for prevention if you are vegan or vegetarian.

What to Expect at Your Appointment

When you come for a B12 injection, bring your GP's letter or prescription. The appointment takes about 10 minutes. Your pharmacist will check your blood pressure and ask about any side effects from previous injections.

The injection itself is painless or nearly painless. You may feel a slight sting, but it passes quickly. There is no recovery time. You can go straight back to work or home.

Some people notice a slight bruise at the injection site, but this is rare and fades within days. A few people report mild headache or dizziness immediately after, but this is uncommon and short-lived.

Common Questions

How long does it take to feel better?

Most people notice improved energy within a few days to a week. Brain fog and mood often improve within two to three weeks. Full recovery of nerve symptoms, if you have them, can take months.

Can I overdose on B12?

No. B12 is water-soluble, so your body excretes what it does not use. Injections are safe even at high doses.

Will I need injections forever?

That depends on the cause. If you have pernicious anaemia, yes, you will need regular injections. If your deficiency was caused by diet or a medication you have now stopped, you may only need a course of injections followed by oral supplements or dietary changes.

Can I get B12 from food instead?

If your deficiency is due to diet, increasing B12-rich foods like meat, fish, eggs, and dairy can help. But if your body cannot absorb B12 properly, food alone will not be enough. Injections work around the absorption problem.

What if I have other symptoms too?

Fatigue is the most common symptom, but B12 deficiency can also cause pins and needles, numbness, mouth ulcers, or mood changes. If you have these alongside tiredness, mention them to your GP or pharmacist. They help confirm the diagnosis.

Do I need a GP referral?

You need a GP blood test first to confirm deficiency. Once you have a diagnosis and your GP agrees injections are appropriate, South Ealing Pharmacy can administer them. Bring your prescription or GP letter.

Is B12 deficiency serious?

Untreated B12 deficiency can damage your nerves over time, causing permanent numbness or weakness. This is why it is important to get tested and treated if you have symptoms. Early treatment prevents complications.

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If you are tired all the time and suspect B12 deficiency, the first step is a blood test from your GP. Once you have a diagnosis, South Ealing Pharmacy in South Ealing can help. We offer B12 injections by appointment, with same-day slots often available. Book your appointment now to start feeling better.