Type 1 diabetes
In type 1 diabetes the body's own immune system destroys the cells in the pancreas that make insulin.
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Medicines commonly prescribed for Type 1 diabetes
For informational purposes only. Always consult a doctor before using any medicine.
Dosage form: INJECTABLE, UnknownActive substance: insulin glargineManufacturer: Sanofi-Aventis Deutschland GmbhPrescription requiredDosage form: INJECTABLE, 100 U/mlActive substance: insulin (human)Manufacturer: Novo Nordisk A/SPrescription requiredDosage form: INJECTABLE, 300 U/mlActive substance: insulin glargineManufacturer: Sanofi-Aventis Deutschland GmbhPrescription required
In type 1 diabetes the body's own immune system destroys the cells in the pancreas that make insulin. Without insulin, glucose cannot get out of the blood and into the cells: there is far too much of it in the bloodstream, the organs are short of energy, and the body starts burning fat instead. It is not caused by sugar, by extra weight or by anything in a child's upbringing. Type 1 diabetes cannot be prevented, and no parent is to blame for it. It most often begins in childhood or early adult life, but it can start at any age. Insulin is needed from the first day and for life, and with it people work, play sport and have children like anyone else.
The first weeks: what gets missed
Type 1 diabetes comes on fast, over weeks and sometimes over a few days. The early signs look so innocuous that they are put down to hot weather, a growth spurt, stress or being tired from school. In a child it looks like this:
- constant thirst: drinking a lot and asking for more all the time;
- passing large amounts of urine often, including at night, getting up several times to go;
- bedwetting in a child who has been dry for a long time: one of the most telling signs of all, and the one most often taken for naughtiness or a step backwards in development;
- losing weight despite a normal or even increased appetite;
- tiredness, listlessness, irritability, slipping at school;
- blurred vision;
- in babies, nappies heavy with urine, poor weight gain, feeding weakly;
- cuts that are slow to heal, repeated thrush, itching in the genital area.
An adult in the same situation is often labelled with type 2 diabetes, because "it does not start like that at your age". If someone is losing weight and their glucose is high, the type of diabetes needs to be established rather than assumed.
The diagnosis itself is straightforward: measuring blood glucose, including with a finger-prick meter, and checking the urine for ketones. It takes minutes and can be done in any consulting room. Waiting for an appointment slot, or for results "next week", is not an option here: with a confirmed high glucose the person is referred to specialist care the same day. It is in exactly that gap, between the first symptoms and getting seen, that most severe presentations happen.
Ketoacidosis: when hours count
With no insulin, the body switches to burning fat and ketones build up in the blood, turning it acid. This is diabetic ketoacidosis, and it develops either at an unrecognised first presentation or later, when someone with diabetes has missed their insulin or fallen ill.
Call an ambulance — in Europe the single number is 112 — if thirst, heavy urination and weakness are joined by any of the following:
- vomiting, especially repeated, and being unable to drink;
- tummy pain, which in children can be severe enough that appendicitis is suspected;
- breath smelling of acetone, like nail varnish remover or overripe fruit;
- deep, slow, noisy breathing, as though they cannot get enough air;
- growing drowsiness, confusion, behaving oddly;
- dry skin and lips, sunken eyes; in a child, floppiness and refusing to drink.
Ketoacidosis responds well to treatment, with fluids and insulin in hospital. What makes it dangerous is sitting it out at home. Do not try to manage it yourself and do not drive a drowsy person there in your own car: call an ambulance and bring all their medicines with you.
Insulin every day, illness included
Insulin is given under the skin, either by pen several times a day or by a pump that delivers it continuously. The usual approach combines a long-acting background insulin with a fast-acting one before meals, the dose worked out from the carbohydrate on the plate and the current glucose. Insulin cannot be swallowed as a tablet: the stomach destroys it.
Two rules, and breaking them is what most often lands people in hospital:
- Background insulin is never skipped, even when you are not eating. It is not there for food; it is there to stop the body burning fat. Missing a day is a direct route to ketoacidosis. If nausea makes eating impossible, the dose is adjusted with your doctor, not dropped.
- During illness the need for insulin usually goes up, not down. A cold, a stomach bug, a fever, an injury, an operation: all of these push glucose higher even when there is no appetite at all. On those days glucose is checked more often, ketones are tested, fluids are kept up and the diabetes team is kept informed.
The injection site is changed every time. Repeatedly injecting into the same spot builds lumps under the skin from which insulin is absorbed unpredictably, and glucose starts swinging for no visible reason. Keep a supply of insulin and equipment at home, and when travelling carry it in hand luggage together with a letter from your doctor.
Hypoglycaemia: spotting it and not panicking
Hypoglycaemia is glucose falling too low, generally below 4 mmol/L. The reasons are simple: more insulin than was needed, a meal missed or delayed, unusual exertion, alcohol. Mild episodes happen to everyone and are not dangerous in themselves as long as they are recognised in time.
The signs are trembling, sweating, a pounding heart, sudden intense hunger, pallor, weak legs, irritability or, the other way round, muddled thinking, difficulty concentrating and headache. A hypo overnight gives itself away through nightmares, sweating and a heavy head in the morning. In small children it more often shows as sudden pallor, tearfulness or unexpected sleepiness.
While the person is conscious: give fast-acting carbohydrate — a glass of juice or ordinary sugary fizzy drink, glucose tablets, a few lumps of sugar. Not chocolate or biscuits: the fat in them slows absorption. Recheck the glucose after fifteen minutes and repeat if it is still low, then follow it with something slower, such as a sandwich or porridge.
If the person is unconscious, cannot swallow or is having a seizure, put nothing in their mouth. No water, no juice, no sugar under the tongue: they will choke. Roll them onto their side, call an ambulance, and if there is glucagon in the house and you have been shown how to use it, give it. Glucagon comes as an injection and as a nasal spray, it is not difficult to use, and the family should be taught in advance, because they are the ones who will be giving it.
Keeping track of glucose
A finger-prick meter is simple and reliable, and everyone still uses one. Readings are taken before meals, before bed, before driving and any time you feel odd — and more often during illness, sport and after alcohol.
Continuous glucose monitoring means a sensor worn on the skin that sends a reading to a phone every few minutes and alarms when glucose is falling or climbing too fast. It shows what finger pricks cannot: overnight dips, the rise after particular meals, and which way the glucose is heading right now. Pumps deliver insulin continuously and dose small amounts more precisely, and some of them work with a sensor and adjust delivery on their own. Availability is not the same everywhere, but it is worth asking your team about, because it makes life noticeably easier, especially for children and for anyone with overnight hypos.
Every few months a glycated haemoglobin test is done: it reflects average glucose over the previous two to three months and says something individual readings cannot. Targets are agreed individually, but broadly the aim is around 4 to 7 mmol/L before meals and up to 9 mmol/L a couple of hours after. Hitting them all the time is impossible, and it is not the point: what matters is the proportion of time spent in range, not perfect numbers.
Food, exercise and alcohol
There is no such thing as a separate "diabetic diet". You can eat what everyone else eats; the skill is knowing how much carbohydrate is in a portion and matching the dose to it. That is taught on structured education courses, and it is the skill that buys freedom: with it you can go to a friend's house, to a restaurant or off on a hike.
- Exercise lowers glucose, both during and for several hours afterwards, sometimes overnight. Check before, during and after; extra carbohydrate or a reduced dose is usually needed beforehand.
- Alcohol is treacherous because it blocks the liver from releasing glucose, so a hypo arrives hours later, often at night, and bystanders mistake it for drunkenness. Do not drink on an empty stomach, eat carbohydrate alongside, check before bed, and stay within the general alcohol guidance where you live.
- Driving is fine provided you can feel a hypo coming and know how to head it off. If you have stopped sensing them, or severe episodes are happening, do not drive until it has been worked through with your team. Check before setting off, keep fast-acting carbohydrate in the car, and stop at the first sign. In most countries you must tell the driving licence authority that you have diabetes treated with insulin.
- Carry fast-acting carbohydrate and identification — a bracelet or a card saying you have type 1 diabetes and take insulin. Teach the people around you to recognise a hypo and to use glucagon; school and workplace should know too.
- Smoking damages blood vessels hardest of all in diabetes, and stopping counts for as much as glucose control does.
What can follow, and how to hold it off
Years of high glucose damage blood vessels and nerves. This is neither a sentence nor an inevitability: complications develop slowly, and everything that prevents them is known and works — steady glucose, normal blood pressure, cholesterol under control, not smoking.
- Eyes. Changes in the retina cause no symptoms for a long time, so the back of the eye is examined regularly, starting in adolescence or a few years after diagnosis according to the rules where you live. Retinopathy found early is treated successfully; found late, it is not.
- Kidneys. The early sign is protein in the urine, which nobody can feel. A urine test and an assessment of kidney function are done yearly.
- Nerves and feet. Numbness, tingling, burning, loss of sensation. The danger is that a small wound or a callus goes unnoticed and turns into an ulcer. Look at your feet daily and have them checked once a year; a wound on the foot that is not healing needs to be seen quickly.
- Heart and circulation. The risk of heart attack and stroke is higher than usual, so blood pressure and cholesterol are treated as seriously as glucose. High glucose also encourages gum disease, which is why the dentist belongs on the list of regular visits.
- Other autoimmune conditions, thyroid disease and coeliac disease in particular, are commoner in type 1 diabetes and are screened for as a matter of routine.
The annual review is not a formality: almost everything on this list is silent in its early stages and is only found when someone goes looking for it.
Online consultation
Almost everything except the emergencies suits a consultation online. If you have noticed thirst, frequent urination or a return of bedwetting in a child, a doctor can tell you which tests to arrange today and where to go. If the diagnosis is already made, they can work through the insulin regimen and carbohydrate counting with you, go over a glucose diary or a sensor download, explain what to do on sick days and when travelling, discuss frequent or overnight hypos, and set out the plan of annual checks. The signs of ketoacidosis — vomiting, tummy pain, acetone on the breath, noisy breathing, drowsiness — do not wait for a consultation: they mean calling an ambulance.
This material is for information only and does not replace medical advice.
Consult with a doctor about Type 1 diabetes
Discuss your symptoms and possible next steps with a doctor online.
Online doctors for Type 1 diabetes
Discuss your symptoms and possible next steps for Type 1 diabetes with a doctor online.
