Nothing has displaced metformin as the first thing tried in type 2 diabetes, and it has been around for decades.
It reduces how much glucose the liver releases and makes cells respond better to the insulin that is already there.
Without prescription, plain packaging. Start low and take it with food, or you will regret it.
In type 2 diabetes the liver is releasing more glucose than it should, particulary overnight — which is why morning readings are often the worst of the day.
At the same time, muscle and fat cells have become less responsive to insulin. The insulin is there; the cells are not listening.
Metformin works on both.
It reduces glucose output from the liver, and it improves how well tissues respond to insulin. It does not force the pancreas to produce more.
That distinction explains its best feature: on its own, it essentially does not cause low blood sugar. There is no extra insulin being pushed out to overshoot.
More than diabetes
Type 2 diabetes, as the usual first treatment
Prediabetes, to delay or prevent progression
Polycystic ovary syndrome, where insulin resistance drives the hormonal picture
Alongside other diabetes medicines, including insulin
In PCOS the logic is indirect but sound. High insulin levels drive the ovaries to produce more androgens, which disrupts ovulation. Improving insulin sensitivity can restore more regular cycles.
Why start low?
The majority of people who abandon metformin do so in the first fortnight, because of the stomach.
Nausea, cramping, diarrhoea, a generally unsettled gut. Unpleasant enough that plenty of people conclude they cannot take it.
Almost all of this is avoidable.
Begin with a low dose, once daily.
Always with food, in the middle of a meal rather than before.
Increase slowly, over weeks rather than days.
If a step is too much, drop back and go slower.
Ask about the extended-release form, which is tolerated better.
Most of the upset settles within a few weeks once the dose is established. Pushing up too fast is the one thing that makes it unbearable.
Vitamin B12 over the long term
Rarely mentioned and worth knowing, because years of use can reduce B12 absorption.
Deficiency causes tiredness, pins and needles in the hands and feet, weakness, sometimes memory problems. All of which are easily put down to the diabetes or to age.
It is a simple blood test and an easy fix. Worth checking periodically if you have been on it for years, especially if you have any tingling in the feet.
When to pause it
A specific and genuinely important point.
Metformin very rarely causes a build-up of lactic acid, and that risk rises in situations where the kidneys are struggling or oxygen delivery is compromised.
Stop it and get advice if you become seriously unwell with vomiting or diarrhoea, develop a severe infection, become dehydrated, or are about to have surgery or a scan involving contrast dye.
Warning signs: unusual deep tiredness, muscle aching, difficulty breathing, abdominal pain, feeling cold, a very slow or irregular pulse.
Rare. But knowing when to pause it is more useful than knowing the mechanism.
Alcohol
Heavy drinking raises the lactic acid risk and also interferes with the liver's ability to release glucose when needed.
Moderate drinking with food is usualy fine. Binge drinking is the pattern that causes problems.
Possible side effects
Nausea, diarrhoea, abdominal cramping — mostly early
Metallic taste
Reduced appetite
Bloating
B12 deficiency with long use
Low blood sugar is not typical on metformin alone, but becomes possible in combination with insulin or sulfonylureas.
Check your feet. Every day.
It sounds excessive until you know why.
Raised blood sugar damages small nerves over time, and sensation in the feet fades so gradually that people do not notice it going. A blister, a stone in the shoe or a small cut then goes unfelt.
Circulation is often poorer too, so the wound heals slowly. A trivial injury turns into a serious problem.
Look at your feet daily, including between the toes and underneath
Use a mirror, or ask someone
Shoes that fit, never tight
Shake out your shoes before putting them on
Do not walk barefoot
Any wound that is not healing quickly gets seen
Ordering without prescription: how it works
Decades of daily use is the typical pattern, so supply continuity is the only real planning question.
Pick the strength and the pack size, put in a delivery address, confirm. Couple of minutes, any time of day, no queue and no conversation across a counter.
It goes out in plain packaging. No pharmacy name on the outside, nothing that hints at what is inside. How long delivery takes depends on where the parcel is headed.
On price it comes down to strength and pack size. Larger packs generally work out better per unit.
Delivery goes anywhere in the UK, in plain outer packaging with no logo and no product name on it. How long it takes depends on where it is heading and which service you picked. Prices are in pounds.
