Starting Saxenda during your first week marks an important phase in medically supervised weight management. As a GLP-1 receptor agonist, Saxenda (liraglutide 3.0 mg) mimics natural hormones that regulate appetite and food intake. Your first week begins with a low starting dose of 0.6 mg daily, designed to minimise side effects whilst allowing your body to adjust. Most patients experience mild gastrointestinal symptoms, particularly nausea, alongside gradual appetite reduction. Understanding what to expect during this initial period—including proper injection technique, common side effects, and when to seek medical advice—helps ensure safe, effective treatment as part of a comprehensive weight management programme incorporating dietary changes and increased physical activity.

What to Expect During Your First Week on Saxenda

Starting Saxenda (liraglutide 3.0 mg) represents an important step in medically supervised weight management. As a glucagon-like peptide-1 (GLP-1) receptor agonist, Saxenda works by mimicking a naturally occurring hormone that regulates appetite and food intake. During your first week, you will begin at a low dose that is gradually increased over subsequent weeks to minimise side effects whilst allowing your body to adjust to the medication.

Saxenda is licensed in the UK for weight management in:

• Adults with a BMI ≥30 kg/m² (obese) or ≥27–<30 kg/m² (overweight) with at least one weight-related comorbidity

• Adolescents aged 12 to <18 years with obesity and body weight above 60 kg

The first week is primarily an adjustment period rather than a time when you will experience maximum therapeutic effect. Most patients notice some reduction in appetite within the first few days, though the full weight loss benefits typically emerge over several weeks as the dose is titrated upwards. It is essential to understand that Saxenda is prescribed as part of a comprehensive weight management programme that includes dietary modification and increased physical activity, not as a standalone treatment.

Key expectations for week one include:

• Mild to moderate gastrointestinal symptoms (particularly nausea)

• Gradual reduction in appetite and food cravings

• Learning the injection technique and establishing a daily routine

• Monitoring for any adverse reactions

Your prescriber should have provided detailed instructions on injection technique and storage requirements. Before first use, store Saxenda in a refrigerator (2–8°C). After first use, the pen can be kept for up to 1 month at room temperature (≤30°C) or refrigerated; do not freeze; keep the pen cap on to protect from light. The medication is administered once daily via subcutaneous injection into the abdomen, thigh, or upper arm. Establishing a consistent time each day helps maintain steady medication levels and supports adherence to treatment.

The Saxenda pen is for single-patient use only. Used needles should be disposed of safely in a sharps bin, which can be obtained from your local pharmacy or council services.

Starting Dose and Titration Schedule in Week One

Saxenda follows a specific dose escalation protocol designed to improve tolerability and reduce the likelihood of gastrointestinal side effects. During your first week, you will use the starting dose of 0.6 mg once daily. This represents only one-fifth of the maintenance dose and serves primarily to allow your body to adapt to the medication's effects on the gastrointestinal system.

The 0.6 mg dose is administered using the Saxenda pre-filled pen, which delivers precise doses through a simple dial mechanism. Each pen contains 18 mg of liraglutide in 3 ml solution (6 mg/ml concentration). At the 0.6 mg dose, a single pen would theoretically last approximately 30 days, though in practice you will increase your dose before then according to the titration schedule. Typically, your first pen will be finished early in week 3 as you increase to higher doses.

The standard licensed titration schedule per the SmPC is:

• Week 1: 0.6 mg daily

• Week 2: 1.2 mg daily

• Week 3: 1.8 mg daily

• Week 4: 2.4 mg daily

• Week 5 onwards: 3.0 mg daily (maintenance dose)

This gradual increase is not optional—it is a clinically important aspect of treatment that significantly reduces the risk of treatment discontinuation due to side effects. If you experience persistent or severe gastrointestinal symptoms at any stage, your prescriber may recommend staying at your current dose for an additional week before increasing further. However, you should not adjust the titration schedule without medical guidance.

If you miss a dose:

• If less than 12 hours have passed since your missed dose, take it as soon as you remember

• If more than 12 hours have passed, skip that dose and take your next dose as usual the following day

• Never take a double dose to make up for a missed dose

• If you miss more than 3 consecutive days, restart at 0.6 mg and follow the titration schedule again

It is crucial to inject Saxenda at approximately the same time each day to maintain consistent blood levels. The medication can be taken with or without food, offering flexibility in timing to suit your daily routine.

Saxenda should not be used in combination with other GLP-1 receptor agonists or other weight-loss medicines.

Common Side Effects in the First Week

During the first week on Saxenda, most patients experience some degree of side effects, predominantly affecting the gastrointestinal system. These effects are generally mild to moderate in severity and tend to diminish as your body adjusts to the medication. Understanding what is normal helps you distinguish between expected reactions and symptoms requiring medical attention.

The most frequently reported side effects in the first week include (frequencies from the SmPC):

• Nausea (affecting approximately 40% of patients initially)

• Diarrhoea (reported by around 20% of users)

• Constipation (affecting approximately 20% of patients)

• Vomiting (occurring in roughly 16% of cases)

• Headache

• Dyspepsia (indigestion)

• Fatigue or dizziness

• Injection site reactions (redness, itching, or mild discomfort)

These side effects result from Saxenda's mechanism of action. As a GLP-1 receptor agonist, liraglutide slows gastric emptying and affects gastrointestinal motility, which contributes to both its appetite-suppressing effects and its gastrointestinal side effects. The low starting dose of 0.6 mg is specifically chosen to minimise these reactions whilst your digestive system adapts.

Most gastrointestinal symptoms are transient, typically peaking within the first few days and gradually improving over 1–2 weeks. However, if you experience severe, persistent, or worsening symptoms, you should contact your prescriber. Severe abdominal pain, particularly if accompanied by vomiting, requires prompt medical assessment to rule out pancreatitis, a rare but serious potential adverse effect. If pancreatitis is confirmed, Saxenda should not be restarted.

Injection site reactions are usually mild and resolve spontaneously. Rotating injection sites between the abdomen, thigh, and upper arm helps minimise local reactions and ensures optimal medication absorption.

If you experience signs of a severe allergic reaction (breathing difficulty, facial/tongue/throat swelling, wheeze or collapse), call 999 immediately.

Managing Nausea and Gastrointestinal Symptoms

Nausea represents the most common side effect during the first week on Saxenda, but several evidence-based strategies can help minimise its impact and improve treatment tolerability. Proactive management of gastrointestinal symptoms significantly increases the likelihood of successfully continuing treatment through the titration phase.

Dietary modifications to reduce nausea:

• Eat smaller, more frequent meals rather than three large meals daily

• Avoid high-fat, greasy, or heavily spiced foods, which slow gastric emptying further

• Choose bland, easily digestible foods such as toast, crackers, rice, or bananas when nausea is present

• Stay well hydrated with small, frequent sips of water throughout the day

• Avoid lying down immediately after eating; remain upright for at least 30 minutes

• Identify and avoid personal trigger foods that worsen symptoms

• Limit alcohol consumption and avoid very large or high-fat meals

The timing of your Saxenda injection may influence symptom severity. Some patients find that injecting in the evening reduces daytime nausea, whilst others prefer morning administration. Experiment to find what works best for you, but maintain consistency once you establish a routine.

For constipation, increase dietary fibre gradually (fruits, vegetables, whole grains), maintain adequate fluid intake (at least 1.5–2 litres daily), and engage in regular physical activity. If constipation persists, speak with your pharmacist about appropriate over-the-counter remedies such as bulk-forming laxatives (e.g., ispaghula husk). Avoid stimulant laxatives unless advised by a healthcare professional.

For diarrhoea, ensure adequate hydration and consider temporarily reducing dietary fibre. Seek medical advice if diarrhoea persists beyond 72 hours, contains blood, or is accompanied by fever, as dehydration can occur rapidly.

When to seek medical advice:

• Severe or persistent vomiting preventing adequate fluid intake

• Signs of dehydration (dark urine, dizziness, reduced urination)

• Severe abdominal pain, particularly in the upper abdomen

• Symptoms that significantly interfere with daily activities

Your prescriber may recommend anti-emetic medication if nausea is particularly troublesome, though this is typically reserved for more severe cases.

Monitoring Your Response and Safety Considerations

Careful monitoring during your first week on Saxenda ensures both safety and optimal treatment outcomes. Your healthcare provider should have conducted baseline assessments before prescribing Saxenda, including measurement of body weight, body mass index (BMI), blood pressure, and potentially blood tests to assess kidney function and glucose metabolism.

Self-monitoring during week one should include:

• Daily adherence tracking: Record each injection to establish routine and identify any missed doses

• Side effect diary: Note the type, severity, and duration of any adverse effects

• Appetite and satiety changes: Observe how the medication affects your hunger and fullness signals

• Injection site assessment: Check for unusual reactions beyond mild, transient redness

Weigh yourself at the same time of day, ideally weekly rather than daily, as day-to-day fluctuations can be misleading and discouraging. Significant weight loss is not expected during the first week at the 0.6 mg dose—this period focuses on tolerability and adjustment.

Important safety considerations specific to Saxenda:

• Pregnancy and breastfeeding: Do not use Saxenda during pregnancy or breastfeeding. If you become pregnant while using Saxenda, stop the medication and contact your prescriber immediately.

• Hypoglycaemia risk: This is uncommon in patients without diabetes. The risk increases if you take sulfonylurea medications; use with insulin is not recommended. Be aware of symptoms (shakiness, sweating, confusion, rapid heartbeat).

• Pancreatitis: Seek immediate medical attention if you develop severe, persistent abdominal pain that may radiate to the back, with or without vomiting. If pancreatitis is confirmed, Saxenda should not be restarted.

• Gallbladder problems: Rapid weight loss can increase gallstone risk; report symptoms of cholecystitis (right upper abdominal pain, particularly after meals).

• Heart rate: Saxenda may increase resting heart rate by 2–3 beats per minute; report palpitations or persistent rapid heartbeat.

• Kidney function: Dehydration from vomiting or diarrhoea can affect kidney function; maintain adequate hydration.

When to seek emergency medical attention:

• Severe allergic reactions (rash, swelling, difficulty breathing) – call 999

• Severe, persistent abdominal pain – seek urgent medical care

• Persistent vomiting preventing fluid intake

• Signs of pancreatitis or gallbladder inflammation

• Symptoms of thyroid tumours (lump in neck, hoarseness, difficulty swallowing)—though extremely rare

Your prescriber should schedule a follow-up review after 4–8 weeks to assess weight loss response, tolerability, and whether continuation of treatment is appropriate. According to the licensed SmPC, Saxenda should be discontinued if patients have not lost at least 5% of initial body weight after 12 weeks on the maintenance dose (3.0 mg). The first week represents the beginning of this therapeutic trial, and open communication with your healthcare team optimises your chances of successful, safe weight management.

If you experience any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in the package leaflet. You can also report side effects directly via the MHRA Yellow Card Scheme at yellowcard.mhra.gov.uk or via the Yellow Card app.

Frequently Asked Questions