Tirzepatide is a first-in-class dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist. It is used to improve blood sugar control in adults with type 2 diabetes mellitus and for long-term weight management in individuals with obesity or overweight and weight-related medical conditions. By mimicking two natural hormones, it helps the body release more insulin, reduces the amount of sugar produced by the liver, and slows down digestion, which promotes a feeling of fullness. It is typically administered as a once-weekly subcutaneous injection.

Tirzepatide contains tirzepatide, a synthetic peptide that represents a significant advancement in metabolic therapy. Unlike previous treatments that target only one hormone receptor, this medicine is a "dual agonist," meaning it activates both GIP and GLP-1 receptors. These receptors are found in areas of the body involved in glucose metabolism and appetite regulation, such as the pancreas, gut, and brain.

The clinical role of Tirzepatide is twofold. In patients with type 2 diabetes, it helps normalise HbA1c levels by stimulating insulin secretion only when blood sugar levels are high, which reduces the risk of hypoglycemia. Simultaneously, it decreases the secretion of glucagon, a hormone that raises blood sugar. In the context of weight management, Tirzepatide acts on the brain’s satiety centres to reduce food cravings and slows gastric emptying, meaning food stays in the stomach longer.

This medication is intended for long-term use as an adjunct to a reduced-calorie diet and increased physical activity. Because it has a long half-life, it is designed for convenient once-weekly dosing. It is delivered via a pre-filled pen or vial for injection under the skin of the abdomen, thigh, or upper arm. Due to its potent effects on the digestive system, the dose is usually started low and gradually increased over several weeks under medical supervision to allow the body to adjust.

Tirzepatide may be indicated by your doctor for:

Type 2 Diabetes Mellitus

To improve glycemic control in adults as an adjunct to diet and exercise.

Chronic Weight Management

For adults with obesity (BMI of 30 kg/m² or greater) or overweight (BMI of 27 kg/m² or greater) who also have at least one weight-related condition, such as hypertension or high cholesterol.

Cardiovascular Risk Reduction

Emerging evidence suggests it may help reduce the risk of major adverse cardiovascular events in patients with metabolic disorders.

Tirzepatide may provide benefits such as:

• Provides a powerful reduction in HbA1c levels, often helping patients reach their glucose targets more effectively than single-hormone therapies.

• Leads to significant and sustained weight loss by reducing appetite and increasing the feeling of fullness.

• Low risk of hypoglycemia (low blood sugar) when used as a standalone therapy.

• Improves various metabolic markers, including blood pressure and cholesterol levels.

• Offers the convenience of once-weekly administration compared to daily medications.

• Helps protect the function of insulin-producing cells in the pancreas over time.

Tirzepatide may cause side effects in some people, although many tolerate it well when used as prescribed.

Common side effects of Tirzepatide may include

• Nausea and vomiting

• Diarrhoea or constipation

• Reduced appetite

• Abdominal pain or discomfort

• Indigestion (dyspepsia)

Uncommon side effects of Tirzepatide may include

• Fatigue or tiredness

• Injection site reactions (redness or itching)

• Hair loss (alopecia)

• Dizziness

Serious side effects that may require immediate medical attention include

• Pancreatitis: Severe, persistent stomach pain that may radiate to the back, with or without vomiting.

• Gallbladder Problems: Pain in the upper right stomach, fever, or yellowing of the skin/eyes.

• Kidney Injury: Significant changes in urine output or swelling of the legs and ankles due to dehydration from vomiting.

• Severe Allergic Reaction: Swelling of the face, lips, or tongue; difficulty breathing; or severe rash.

• Hypoglycemia: While rare alone, it can occur if used with insulin or sulfonylureas.

• Always consult your doctor if you notice any persistent or concerning reactions while using Tirzepatide.

Use Tirzepatide exactly as directed by your doctor based on the prescribed form.

• Administer the dose once a week, on the same day each week, at any time of day.

• Inject subcutaneously (under the skin) in the abdomen, thigh, or upper arm.

• Rotate injection sites with each dose to reduce the risk of skin irritation.

• It can be taken with or without food.

• Follow the specific instructions provided with your pre-filled pen or vial; ensure you understand how to use the device before your first dose.

• If you need to change the day of your weekly injection, ensure there are at least 3 days (72 hours) between doses.

Tirzepatide works by acting as an agonist at both GIP (Glucose-dependent Insulinotropic Polypeptide) and GLP-1 (Glucagon-Like Peptide-1) receptors. Naturally, these hormones are released by the gut after eating. GIP helps the body manage energy balance and supports insulin secretion, while GLP-1 slows stomach emptying and signals the brain that you are full. By activating both pathways, Tirzepatide enhances the body’s ability to lower blood sugar in a glucose-dependent manner (meaning it only works when sugar is present) and significantly suppresses appetite. This combined action addresses the underlying hormonal imbalances associated with type 2 diabetes and obesity.

• To reduce nausea, eat smaller meals, avoid high-fat or greasy foods, and stop eating as soon as you feel full.

• Stay well-hydrated by sipping water throughout the day, especially if you experience vomiting or diarrhoea.

• If you use birth control pills, discuss alternative methods with your doctor, as this medicine may temporarily affect the absorption of oral contraceptives.

• Set a weekly reminder on your phone to ensure you take your dose on the same day each week.

• Do not share your injection pen with others, even if the needle has been changed, to prevent the spread of infection.

• Store Tirzepatide in a refrigerator between 2°C and 8°C (36°F to 46°F).

• Do not freeze; if the medication has been frozen, it must be discarded.

• Protect from light by keeping the pens in their original carton.

• Keep out of the reach of children and pets.

• High-Fat Meals (CAUTION): Consuming very fatty or large meals may worsen the nausea and stomach discomfort associated with this medication.

• General Diet (BENEFICIAL): A diet rich in lean proteins and fiber is recommended to support metabolic health while on this treatment.

• Insulin and Sulfonylureas (MODERATE): Combining Tirzepatide with these can increase the risk of hypoglycemia; your doctor may need to adjust your doses.

• Oral Medications (CAUTION): Because this medicine slows stomach emptying, it may affect how quickly other pills are absorbed into your system.

• Oral Contraceptives (CAUTION): The effectiveness of birth control pills may be reduced; use of a backup method is often advised for the first few weeks of treatment or after dose increases.

• Thyroid Cancer History (SEVERE): Do not use if you or your family have a history of Medullary Thyroid Carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2).

• Pancreatitis (CAUTION): Inform your doctor if you have ever had inflammation of the pancreas.

• Severe Gastrointestinal Disease (CAUTION): Use with care in patients with slow digestion (gastroparesis) or other severe stomach issues.

• Diabetic Retinopathy (CAUTION): Rapid improvement in glucose

An overdose of Tirzepatide is likely to cause severe nausea, vomiting, and abdominal pain. If an overdose is suspected, contact your healthcare provider immediately. Supportive care and monitoring of blood sugar levels may be necessary.

If you miss a dose, take it as soon as possible within 4 days (96 hours) after the missed dose. If more than 4 days have passed, skip the missed dose and take your next dose on the usual scheduled day. Do not take two doses within 3 days of each other.