Type 2 diabetes: symptoms, diagnosis and treatment

What are the symptoms?

The classic symptoms are thirst that is not satisfied by drinking, passing water more often and especially at night, tiredness, unexplained weight loss and blurred vision. Others include itching in the genital area or recurrent thrush, cuts and grazes that are slow to heal, and repeated skin or urinary infections.

The important point is how often there are none at all. Type 2 diabetes is frequently found on a blood test done for another reason, and by then it may have been present for years. That is why risk matters as much as symptoms, and why the absence of symptoms is not reassurance.

Some people are diagnosed after a complication rather than before it: numbness or burning in the feet, a change in vision, or a foot ulcer that will not heal. Any of those in someone not known to have diabetes is a reason to have the test done rather than to wait and see.

Who is at higher risk?

Risk rises with age and with weight, particularly weight carried around the waist, and it is higher in people with a parent or sibling who has the condition. Some ethnic groups develop it earlier and at a lower body weight, which is why thresholds used elsewhere do not transfer neatly.

Other well-established associations are high blood pressure, raised cholesterol or triglycerides, polycystic ovary syndrome, a history of diabetes during pregnancy or a large baby, inactivity, disturbed or short sleep, and long-term treatment with steroids or certain other medicines.

A previous result described as prediabetes, impaired glucose tolerance or impaired fasting glucose is the single most useful warning you can be given, because it identifies a period during which progression can often be slowed or prevented. It deserves a plan and a repeat test rather than filing away.

Malta has a high recorded prevalence of both obesity and type 2 diabetes, so a family history here is common rather than unusual. That is an argument for getting tested, not for fatalism.

How is it diagnosed?

Three tests are in general use: a fasting blood glucose, glycated haemoglobin (HbA1c), which reflects average blood sugar over the preceding weeks, and an oral glucose tolerance test, in which glucose is measured before and after a measured sugary drink.

Each is interpreted against the diagnostic cut-off in use by the laboratory that reports it, and your doctor makes the interpretation. We deliberately do not print threshold figures here: they belong to the report in front of your doctor, and a number quoted from a website is exactly how people talk themselves into or out of a diagnosis they have not got.

One rule is worth knowing. A single abnormal result in someone without symptoms is normally repeated before a diagnosis is made, because glucose values move with illness, with stress and with some medicines. Where symptoms are clearly present, one unequivocal result may be enough.

A finger-prick meter bought over the counter is not a diagnostic test. It is useful for monitoring once a diagnosis exists and a doctor has said what to do with the readings; used as a screening tool it produces anxiety rather than answers.

What does treatment involve?

Treatment has two halves that work together, and neither replaces the other. The first is what you eat, how much you move, your weight and your sleep. Modest, sustained weight loss changes blood sugar more than most people expect, and in some people diagnosed recently it can bring values back into the normal range.

The second is medicines. Metformin is usually the first one offered, and our page on /medicines/metformin/ describes it in more detail; loose stools and diarrhoea early on are common and usually settle, and the slow-release form suits some people better. Several other classes exist and are chosen according to your kidney function, your weight, your heart, and whether you have had cardiovascular disease: the SGLT2 inhibitors, as on /medicines/jardiance/, the DPP-4 inhibitors, as on /medicines/januvia/, and the GLP-1 medicines discussed on /weight-loss-injections/ are the groups you will hear named. Insulin is used when it is needed, at any stage.

Which combination fits you is a clinical decision that depends on your results and your other conditions. It is not a ladder everyone climbs in the same order, and it is reviewed as things change.

Our category page /diabetes-and-blood-sugar/ sets out how the common medicines differ.

Which checks matter, and how often

Blood sugar control is only one of the numbers. Blood pressure and cholesterol carry at least as much weight in the risk of heart attack and stroke, and treating them is a large part of treating diabetes well.

The checks that make up ordinary care are HbA1c at intervals set by your doctor, blood pressure, a lipid profile, kidney function including a urine test for protein, an eye examination for retinal changes, and an examination of the feet including the circulation and the sensation in them. Weight, smoking status and mood belong on the list as well.

Keep your own copy of the results with their dates. That record is what lets any doctor continue your treatment sensibly, and it is what makes an assessment of a repeat request possible at all: a prescription written against a result from two years ago is written against nothing.

Home glucose monitoring is useful for some treatments and unnecessary for others. Ask what the readings are supposed to change before buying strips, because the answer decides whether measuring helps you or simply worries you.

Warning signs that need attention without delay

Very high blood sugar with vomiting, deep or rapid breathing, abdominal pain, a fruity smell on the breath, drowsiness or confusion is an emergency. So is marked dehydration with confusion in an older person. Call 112 or go to an accident and emergency department.

Low blood sugar matters for people taking insulin or a sulfonylurea: sweating, shaking, hunger, confusion or aggression that comes on quickly. Treat it with fast-acting sugar and then something starchy, and tell your doctor if it is happening repeatedly, because the treatment needs adjusting.

A foot problem in someone with diabetes is urgent rather than routine. A break in the skin, a blister, redness, swelling, a bad smell or an area that has changed colour needs to be seen within days, not weeks, and a foot that is cold, painful and pale needs to be seen immediately.

A sudden change in vision, chest pain, one-sided weakness or difficulty speaking are emergencies in their own right and are more common in people with diabetes.

Living with type 2 diabetes

The condition rewards routine rather than intensity. Eating patterns that are sustainable beat diets that are not; regular activity most days beats occasional exertion; sleep and stress affect glucose more than people credit.

Alcohol interacts with several treatments and with low blood sugar, and it is worth asking how it fits your particular medicines rather than assuming. Illness raises blood sugar even when you are eating less, and some medicines need to be paused during dehydration, vomiting or diarrhoea; ask your doctor for those rules in advance, because they are needed at the moment you are least able to go looking for them.

Vaccination against influenza and other infections is generally advised, since infection both worsens control and is worse in people with diabetes. Smoking multiplies every cardiovascular risk the condition carries, so stopping it does more than any single tablet.

Finally, ask about driving rules, travel and fasting if they apply to you, well before they become relevant. All three are manageable with planning and awkward without it.