What is type 1 diabetes?

Type 1 diabetes occurs when the immune system destroys the insulin-producing cells in the pancreas. Without insulin, blood glucose levels rise quickly and can become dangerous.

Key features:

  • Autoimmune condition
  • Not caused by lifestyle factors
  • Requires insulin from diagnosis
  • Can develop at any age

This is different from type 2 diabetes, which is primarily related to insulin resistance.

How type 1 diabetes commonly presents

Symptoms often develop over days or weeks and may include:

  • Excessive thirst
  • Frequent urination
  • Weight loss
  • Fatigue
  • Blurred vision

In some cases, people present acutely unwell with diabetic ketoacidosis (DKA), which is a medical emergency.

Type 1 diabetes and diagnosis

Diagnosis is usually made urgently using blood glucose testing and supported by further specialist assessment.

GPs play a key role in:

  • Recognising symptoms early
  • Arranging urgent referral when type 1 diabetes is suspected
  • Supporting patients before and after diagnosis

Type 1 diabetes should always be considered in people with rapid onset symptoms, particularly if weight loss is present.

The role of primary care in type 1 diabetes

Diagnosis is usually made urgently using blood glucose testing and supported by further specialist assessment.

GPs play a key role in:

  • Recognising symptoms early
  • Arranging urgent referral when type 1 diabetes is suspected
  • Supporting patients before and after diagnosis

Type 1 diabetes should always be considered in people with rapid onset symptoms, particularly if weight loss is present.

The role of primary care in type 1 diabetes

While specialist teams oversee insulin management, GPs support people with type 1 diabetes through:

  • Ongoing medical care for other conditions
  • Medication reviews
  • Monitoring blood pressure and cholesterol
  • Managing intercurrent illness
  • Mental health support
  • Coordination of care between services

Primary care provides continuity alongside specialist input.

Monitoring and routine checks

People with type 1 diabetes are usually offered regular reviews that may include:

  • HbA1c monitoring
  • Blood pressure checks
  • Cholesterol testing
  • Kidney function tests
  • Foot and eye screening

These checks help reduce long-term complications.

Type 1 diabetes and illness

Intercurrent illness can significantly affect blood glucose control.

During illness:

  • Blood glucose may rise unpredictably
  • Insulin requirements may change
  • Risk of dehydration increases

GPs can provide advice on sick-day rules and when urgent review is needed.

Mental wellbeing and type 1 diabetes

Living with type 1 diabetes requires constant attention and can affect mental health.

People may experience:

  • Diabetes distress
  • Anxiety around glucose control
  • Burnout from long-term self-management

Primary care plays an important role in recognising and supporting mental wellbeing alongside physical health.

When to seek urgent medical help

Seek urgent help if someone with type 1 diabetes experiences:

  • Persistent vomiting
  • Severe abdominal pain
  • Rapid breathing
  • Confusion or drowsiness
  • Very high blood glucose with ketones
  • Signs of dehydration

These may indicate diabetic ketoacidosis and require emergency assessment.


Further Reading and Hub Links

Visit our Diabetes and Endocrine Health hub or browse more health topics in the AccessGP Knowledge Base.

If you have type 1 diabetes and would like support with general health concerns, illness management or coordination of care, an online GP appointment can help.

Last reviewed by Dr Zamiel Hussain, GMC registered GP
Updated: 25 January 2026