Diabetes Medications Prescribed by UK-Registered Doctors

Type 2 diabetes is a chronic metabolic condition characterised by insulin resistance and progressive beta-cell dysfunction, leading to sustained hyperglycaemia.

It accounts for approximately 90% of all diabetes cases in the UK, with prevalence rising sharply due to increasing obesity rates, an ageing population, and greater diagnostic awareness.

Current UK prevalence: 4.3 million people diagnosed with diabetes (90% type 2), with an estimated 1.2 million living with undiagnosed type 2 diabetes. A further 2.

4 million are classified as at high risk (HbA1c 42-47 mmol/mol, termed non-diabetic hyperglycaemia or prediabetes).

The pathophysiology involves a "twin cycle" of fat accumulation in the liver and pancreas.

Hepatic insulin resistance drives increased glucose output, while pancreatic fat deposition impairs beta-cell insulin secretion.

As beta-cell function declines over time, hyperglycaemia worsens, creating a vicious cycle of glucotoxicity and lipotoxicity.

Risk factors:

• Obesity (BMI 30+) increases risk 7-fold; BMI 35+ increases risk 20-fold
• South Asian, Black African, and Black Caribbean ethnicity — 2-4 times higher risk at lower BMI thresholds
• Family history (first-degree relative with type 2 diabetes doubles risk)
• Previous gestational diabetes (50% develop type 2 within 10 years)
• Physical inactivity, hypertension, dyslipidaemia, and polycystic ovary syndrome

Diagnosis requires one of the following on two separate occasions (or once if symptomatic):

• HbA1c 48 mmol/mol (6.5%) or above
• Fasting plasma glucose 7.0 mmol/L or above
• Random plasma glucose 11.1 mmol/L or above with symptoms

Complications of poorly controlled diabetes are extensive:

• Microvascular: retinopathy (leading cause of blindness in working-age adults), nephropathy (20-30% of dialysis patients have diabetic kidney disease), and neuropathy (affecting 50% of people with diabetes over time)
• Macrovascular: 2-4 fold increased risk of cardiovascular disease, peripheral arterial disease, and stroke
• Other: increased infection susceptibility, foot ulceration (lifetime risk 25%), and lower limb amputation

NICE guideline NG28 provides a structured treatment algorithm for type 2 diabetes, emphasising individualised targets and medication selection based on cardiovascular risk, renal function, BMI, and patient preference.

First-line: Metformin

Metformin remains the cornerstone of type 2 diabetes treatment worldwide. It reduces hepatic glucose output, improves insulin sensitivity in peripheral tissues, and has a modest anorexigenic effect.

Standard dosing: start at 500 mg once daily with food, titrate over 4-6 weeks to 1 g twice daily (maximum 2 g daily).

Metformin benefits:

• HbA1c reduction: 11-15 mmol/mol (1.0-1.5%)
• Weight neutral or modest weight loss (1-2 kg)
• Cardiovascular benefit demonstrated in the UKPDS (39% reduction in MI risk in overweight patients)
• Very low hypoglycaemia risk as monotherapy
• Costs approximately £1.50 per month

Metformin side effects: GI intolerance (nausea, diarrhoea, bloating) affects 20-30% of patients.

Modified-release (MR) formulation reduces GI effects by 50% and should be offered to patients who cannot tolerate immediate-release.

Rare but serious: lactic acidosis (incidence 3-10 per 100,000 patient-years), almost exclusively in patients with significant renal impairment (eGFR below 30).

B12 deficiency occurs in 5-10% of long-term users — check levels every 2-3 years.

Second-line options (added when HbA1c rises above 58 mmol/mol on metformin monotherapy):

SGLT2 inhibitors (empagliflozin 10-25 mg, dapagliflozin 10 mg, canagliflozin 100-300 mg) block glucose reabsorption in the proximal tubule, causing glycosuria. HbA1c reduction: 7-10 mmol/mol.

Additional benefits: weight loss 2-3 kg, systolic BP reduction 4-6 mmHg, reduced heart failure hospitalisation, and renal protection.

The EMPA-REG OUTCOME trial demonstrated a 38% reduction in cardiovascular death with empagliflozin.

NICE now recommends SGLT2 inhibitors early in the treatment pathway for patients with established cardiovascular disease, heart failure, or chronic kidney disease.

DPP-4 inhibitors (sitagliptin 100 mg, linagliptin 5 mg, alogliptin 25 mg) enhance incretin hormone levels, stimulating insulin secretion and suppressing glucagon. HbA1c reduction: 5-8 mmol/mol.

Weight neutral. Well tolerated. No cardiovascular benefit demonstrated in outcome trials, but no harm either.

Sulfonylureas (gliclazide 40-160 mg twice daily) stimulate insulin secretion from beta-cells. HbA1c reduction: 11-15 mmol/mol.

Inexpensive but cause weight gain (2-3 kg) and hypoglycaemia (15-20% of patients). Increasingly being displaced by SGLT2 inhibitors and GLP-1 agonists.

GLP-1 receptor agonists have transformed type 2 diabetes management, offering potent glycaemic control, significant weight loss, and cardiovascular protection in a single medication class.

Available GLP-1 agonists in the UK:

• Semaglutide (Ozempic) 0.25-1.0 mg subcutaneous injection once weekly. HbA1c reduction: 13-17 mmol/mol. Weight loss: 4-6 kg. The SUSTAIN-6 trial showed 26% reduction in major adverse cardiovascular events.
• Dulaglutide (Trulicity) 0.75-4.5 mg once weekly. HbA1c reduction: 10-15 mmol/mol. Weight loss: 2-4 kg. Cardiovascular benefit demonstrated in the REWIND trial.
• Liraglutide (Victoza) 0.6-1.8 mg daily injection. HbA1c reduction: 10-13 mmol/mol. Weight loss: 2-3 kg. The LEADER trial showed 13% reduction in MACE.
• Oral semaglutide (Rybelsus) 3-14 mg once daily — the first oral GLP-1 agonist, taken 30 minutes before breakfast with no more than 120 mL of water. HbA1c reduction comparable to injectable semaglutide 0.5 mg.

NICE recommends GLP-1 agonists when:

• HbA1c remains above 58 mmol/mol on dual oral therapy
• BMI is 35 or above (or lower if weight loss would benefit obesity-related comorbidities)
• In patients with established atherosclerotic cardiovascular disease (semaglutide, liraglutide, or dulaglutide specifically)

GLP-1 agonists must be continued only if HbA1c falls by at least 11 mmol/mol and body weight decreases by at least 3% within 6 months.

Otherwise, NICE mandates discontinuation and an alternative approach.

Side effects are predominantly gastrointestinal:

• Nausea: 15-40% (most common during dose titration, usually resolves by week 4-8)
• Vomiting: 5-15%
• Diarrhoea: 10-20%
• Injection site reactions: 2-5% (mild and transient)
• Pancreatitis: rare (incidence under 0.3%), but patients should report severe abdominal pain

Insulin therapy remains necessary when oral and injectable non-insulin therapies are insufficient or when HbA1c is very high at diagnosis (above 75 mmol/mol with symptoms).

NICE recommends basal insulin (NPH insulin or long-acting analogues such as insulin glargine or insulin degludec) as the initial insulin regimen, added to metformin.

GLP-1 agonists can be combined with basal insulin, providing better weight outcomes than adding bolus insulin.

Combination considerations:

• GLP-1 agonist + metformin + SGLT2 inhibitor is an increasingly used triple therapy offering complementary mechanisms, substantial HbA1c reduction, weight loss, and cardiovascular/renal protection
• Avoid combining GLP-1 agonists with DPP-4 inhibitors (overlapping mechanism, no added benefit)
• Reduce sulfonylurea dose when adding GLP-1 agonist to prevent hypoglycaemia

Lifestyle modification is the foundation of type 2 diabetes management and should be reinforced at every clinical contact.

NICE recommends structured education (such as the DESMOND or X-PERT programmes) for all newly diagnosed patients.

Dietary management:

There is no single "diabetes diet." The evidence supports several approaches:

• Mediterranean diet: associated with 30% reduction in cardiovascular events (PREDIMED trial) and improved glycaemic control
• Low-carbohydrate diets (under 130 g carbohydrate per day): effective for short-term glycaemic improvement and weight loss; Diabetes UK acknowledges low-carb as a valid management option
• Calorie restriction: the DiRECT trial demonstrated that a structured very-low-calorie diet (850 kcal/day for 12-20 weeks) achieved diabetes remission (HbA1c below 48 mmol/mol off medication) in 46% of participants at 12 months

Practical dietary principles:

• Choose low glycaemic index carbohydrates (whole grains, legumes, most fruits)
• Distribute carbohydrate intake evenly across meals to avoid postprandial glucose spikes
• Protein intake 1.0-1.5 g/kg body weight to preserve lean mass during weight loss
• Fibre intake 30 g daily (reduces HbA1c by approximately 2-3 mmol/mol independently)
• Limit free sugars to under 5% of energy intake (approximately 30 g/day)

Physical activity:

• 150 minutes per week of moderate-intensity aerobic exercise (brisk walking, cycling)
• Resistance training 2-3 sessions per week — improves insulin sensitivity independently of weight loss
• Break up prolonged sitting every 30 minutes with light activity — reduces postprandial glucose by 20-30%
• Exercise timing: post-meal walks (10-15 minutes after eating) effectively blunt glucose excursions

HbA1c targets (NICE NG28):

• On lifestyle alone or metformin monotherapy: 48 mmol/mol (6.5%)
• On dual therapy including a drug that causes hypoglycaemia (sulfonylurea, insulin): 53 mmol/mol (7.0%)
• Individualise targets for elderly, frail patients, or those with limited life expectancy: 58-64 mmol/mol may be appropriate to avoid hypoglycaemia
• Tighter control (below 42 mmol/mol) is the target for diabetes remission

Self-monitoring of blood glucose (SMBG) is recommended for patients on insulin or sulfonylureas.

Continuous glucose monitoring (CGM) is increasingly available and provides detailed glycaemic data including time in range (target 3.9-10.0 mmol/L for more than 70% of the time).

Structured diabetes care follows the NICE-recommended annual review cycle, complemented by more frequent monitoring when treatment is being adjusted.

Regular screening for complications enables early intervention that preserves quality of life.

Routine monitoring schedule:

• HbA1c: every 3-6 months until stable, then every 6 months
• Renal function (eGFR and urine albumin:creatinine ratio): annually (every 3-6 months if CKD or SGLT2 inhibitor use)
• Lipid profile: annually (most patients with type 2 diabetes qualify for statin therapy under NICE)
• Liver function: baseline and periodically (fatty liver disease affects 70% of type 2 diabetes patients)
• Foot examination: annually by trained professional, more frequently if neuropathy or vascular disease present
• Diabetic eye screening: annually via the NHS Diabetic Eye Screening Programme
• Blood pressure: at every diabetes review (target below 140/90 mmHg, or below 130/80 if kidney disease)

Medication-specific monitoring:

• Metformin: B12 levels every 2-3 years (deficiency prevalence 5-10%); withhold if eGFR drops below 30
• SGLT2 inhibitors: monitor for genital mycotic infections (10-15% of women, 3-5% of men), urinary tract infections, and volume depletion in elderly patients. Rare risk of diabetic ketoacidosis (DKA) even at near-normal glucose levels (euglycaemic DKA) — withhold during acute illness, surgery, or fasting
• GLP-1 agonists: monitor weight and HbA1c at 6 months to assess continuation criteria
• Sulfonylureas: educate about hypoglycaemia recognition and management; driving implications under DVLA guidance
• Insulin: structured self-monitoring or CGM; driving rules (must check glucose before driving and every 2 hours on long journeys)

DVLA driving regulations:

• Patients on insulin or sulfonylureas must notify the DVLA
• Group 1 (car/motorcycle): blood glucose must be above 5.0 mmol/L before driving
• Group 2 (lorry/bus): more stringent requirements; regular medical review required

Sick day rules are critical patient education:

• Never stop metformin, GLP-1 agonists, or SGLT2 inhibitors in response to reduced food intake during illness — but temporarily withhold SGLT2 inhibitors during acute illness due to DKA risk
• Increase blood glucose monitoring frequency during illness
• Maintain fluid intake; contact a healthcare professional if blood glucose exceeds 15 mmol/L persistently or if unable to eat for more than 24 hours
• Patients on insulin must never stop insulin during illness — dose adjustment may be needed

Dr. Presc provides repeat diabetes prescriptions for patients with established, stable type 2 diabetes under regular GP or specialist review.

New diagnoses and treatment initiations require face-to-face assessment.