Your First Month on Weight Loss Injections Over 70

Posted on October 9, 2026 by Sally-Anne Turner

You’ve made the decision to try weight loss injections. Perhaps your GP has recommended treatment to support your weight management, or you’ve watched a friend regain mobility and energy. Now you’re standing at the threshold of treatment, feeling a mix of hope and apprehension. What actually happens in that first month? Will you feel unwell? How quickly will you see results? What if something goes wrong?

Your first month on weight loss medication is an introduction to treatment. It’s not about dramatic, rapid weight loss – it’s about allowing your body to adjust gradually while your medical team monitors how you’re responding. For people over seventy, this initial period may require additional attention. Factors such as existing health conditions, frailty, nutritional needs and other medications can influence how treatment is managed.

This guide walks you through what to expect in your first four weeks on Wegovy or Mounjaro. You’ll learn what happens during your initial assessment, how the starting dose works, what changes you might notice in your appetite and eating patterns, which side effects to watch for, and when to contact your medical team.

For broader context about weight loss injections after seventy, including long-term considerations and muscle preservation strategies, see our Weight Loss Injections for Over-70s: A Complete Guide.

Before You Start: The Comprehensive Medical Assessment

Your journey doesn’t begin with your first injection. It starts with a NICE backed medical assessment designed to determine whether treatment is appropriate for you and establish baseline measurements to guide your care.

Medical History Review and Risk Assessment

Your clinician will review your medical history, including existing health conditions and how they’re currently managed. If you have type 2 diabetes, they’ll consider your blood glucose control, current medications and any diabetes-related complications.

Your cardiovascular health may also receive particular attention. Have you had a heart attack or stroke? Do you have heart failure or angina? These questions help your medical team understand your overall health and whether additional assessment or monitoring is needed.

Digestive health history matters too. Have you had gallstones or gallbladder problems? Any history of pancreatitis? Severe acid reflux or gastroparesis? These conditions require careful consideration, and some may make particular weight loss injections unsuitable.

Medication Review and Interaction Assessment

Every medication you take – prescription, over-the-counter and supplements – should be documented.

Your clinician will pay particular attention to diabetes medications, especially insulin and sulfonylureas, as these can increase the risk of hypoglycaemia when used alongside certain weight loss injections. Your existing treatment may need reviewing or adjusting.

Blood pressure medications may also require monitoring, particularly if your blood pressure changes during weight loss treatment.

If you’re taking warfarin, additional monitoring may be appropriate, particularly when starting or increasing tirzepatide. Diuretics also require consideration because dehydration can affect kidney function and fluid balance.

Your clinician may coordinate with your GP or other healthcare professionals to ensure your weight loss treatment is appropriate alongside your existing medicines.

Physical Examination and Baseline Measurements

Your initial assessment may include measurements such as weight, height, body mass index (BMI), waist circumference and blood pressure.

For older adults, mobility, muscle strength and frailty are also important considerations. These assessments help determine whether weight loss treatment is appropriate or whether maintaining your current weight and physical function may be a better goal.

Remember, weight loss isn’t necessarily beneficial for everyone. If you’re significantly frail or at risk of malnutrition, preserving weight, strength and nutritional health may be more appropriate.

Blood Tests and Laboratory Work

Your clinician may recommend blood tests based on your medical history and current health.

These can include kidney function, liver function and HbA1c if you have diabetes. Other investigations may be appropriate depending on your medical history, symptoms and existing medications.

Kidney function is particularly relevant because dehydration associated with vomiting or diarrhoea can cause complications, especially in people with existing kidney problems.

Baseline investigations can help identify issues requiring attention and provide useful information for ongoing monitoring.

Setting Realistic Goals and Expectations

Your initial consultation includes an important discussion about goals. What are you hoping to achieve?

Many people over seventy aren’t aiming for dramatic weight loss. They may want better diabetes control, reduced joint pain, improved mobility or simply to feel more energetic.

Your clinician will help you understand realistic expectations. Clinical trials have demonstrated substantial average weight loss with semaglutide and tirzepatide, but individual results vary. Importantly, older adults, particularly those with significant frailty or multiple health conditions, may not be adequately represented in every trial.

You’ll also discuss the commitment required. Weight loss injections are used alongside dietary changes and physical activity, with ongoing clinical review to determine whether treatment remains suitable.

Week One: Your First Injection and Initial Adjustments

The first injection often feels like a significant milestone. You’ve completed your assessment, received your prescription and are ready to begin.

Learning to Self-Inject

If you’ve never self-injected before, the prospect might feel daunting. Modern injection pens are designed to make administration manageable, although the instructions differ between products.

Your clinical team should explain how to prepare and use your particular pen, choose an injection site and dispose of needles safely.

Both Wegovy and Mounjaro are injected into the tissue just beneath the skin, with approved injection sites including the abdomen, thigh or upper arm. Injection sites should be rotated.

Always follow the patient information leaflet and instructions supplied with your specific pen.

If you have arthritis in your hands or vision problems, your clinician can discuss whether you need assistance with injections.

The Starting Dose: Why We Begin Low

The usual starting doses are:

Wegovy: 0.25 mg once weekly.

Mounjaro: 2.5 mg once weekly.

These are introductory doses intended to help your body adjust to treatment and reduce the likelihood of gastrointestinal side effects.

They aren’t the usual maintenance doses, although some people may notice appetite changes or weight loss during the initial weeks.

Starting at the recommended dose is important regardless of age. Your clinician will also consider any individual health concerns that could affect how well you tolerate treatment.

Don’t expect dramatic changes in your first week. Some people notice subtle appetite changes, while others notice very little initially.

What You Might Notice in Week One

Everyone responds differently to their first week on weight loss injections.

Some people experience no noticeable side effects. Others develop nausea, diarrhoea, constipation or abdominal discomfort.

Appetite changes can also begin at the starting dose. You might find yourself thinking about food less often or feeling satisfied with smaller portions.

Some people experience tiredness or fatigue, although this should not automatically be assumed to be a normal adjustment if it is severe or persistent.

If symptoms interfere with eating, drinking or everyday activities, contact your clinical team.

Eating in Week One: Practical Strategies

Even though your appetite might not change dramatically at the starting dose, it’s worth beginning good eating habits immediately.

Include sources of protein throughout the day, such as chicken, fish, eggs, dairy products or legumes. Adequate protein intake is particularly important for older adults because weight loss can involve losing muscle as well as fat.

Eat slowly and pay attention to fullness signals. Smaller meals may help if you experience nausea or feel full sooner than expected.

Stay adequately hydrated, particularly if you’re experiencing gastrointestinal side effects. Your individual fluid requirements may differ if you have heart failure, kidney disease or have been advised to restrict fluids.

Monitoring in Week One

If you have diabetes and take insulin or sulfonylureas, your clinician may recommend additional blood glucose monitoring and adjustments to your existing diabetes treatment.

According to the NHS, blood glucose readings below 4 mmol/L indicate hypoglycaemia and should be managed according to your diabetes care plan.

If you take blood pressure medication, your clinician may recommend monitoring your blood pressure, particularly if you experience dizziness.

Keep a simple record of how you’re feeling, including side effects, appetite changes and any concerns.

Weeks Two Through Four: Settling Into Treatment

After your first injection, you normally continue with the same starting dose for the remainder of the first four weeks, in line with the prescribed treatment schedule.

How Side Effects Typically Evolve

If you experienced nausea in your first week, it may improve as your body adjusts. However, side effects can vary in duration and severity.

Some people experience gastrointestinal symptoms later in treatment or following dose increases.

Constipation can also occur. Eating a balanced diet containing appropriate sources of fibre, staying adequately hydrated and remaining physically active may help.

If constipation becomes persistent or uncomfortable, speak to your pharmacist or prescribing clinician before taking additional medication.

Appetite Changes Become More Noticeable

By weeks two through four, some people notice more pronounced appetite changes.

You might find that meals you previously finished easily now leave you feeling full sooner. You may also notice changes in snacking habits or food cravings.

However, not everyone experiences these changes during the first month, and the absence of noticeable appetite suppression doesn’t necessarily mean treatment will be unsuccessful.

It’s important to continue eating enough to meet your nutritional needs, even if your appetite decreases.

For older adults, inadequate food intake can increase the risk of malnutrition and muscle loss.

Early Weight Loss: What’s Normal?

Weight loss in the first month varies considerably between individuals.

Some people experience weight loss during the introductory phase, while others see little change.

Early changes in body weight can also reflect changes in fluid balance, rather than body fat alone.

If you lose little or no weight during your first month, don’t automatically assume the medication isn’t working. Your clinician will assess your response over time and review your treatment according to the relevant prescribing guidance.

Managing Your Other Medications

During the first month, your clinician may review blood glucose and blood pressure readings where appropriate.

If you have diabetes, weight loss injections may improve blood glucose control. However, combining treatment with insulin or sulfonylureas can increase the risk of hypoglycaemia.

Your clinician may recommend adjustments to these medicines based on your individual circumstances.

If your blood pressure is consistently lower than usual, or you’re experiencing dizziness when standing, your blood pressure medication may also need reviewing.

Don’t stop or change prescribed medication independently.

Physical Activity and Energy Levels

Some people feel more energetic as treatment progresses, while others experience tiredness.

Try to maintain an appropriate level of physical activity during your first month.

Walking, adapted exercises and other activities suited to your mobility can support physical health.

Muscle-strengthening exercises are particularly important for older adults undergoing weight loss because they can help preserve strength and physical function.

If you have mobility limitations, frailty or existing health conditions, ask your healthcare professional about suitable exercises.

Common Concerns and How to Address Them

Certain concerns come up repeatedly during the first month of weight loss injections.

Persistent Nausea: When to Seek Help

Mild nausea is a recognised side effect of Wegovy and Mounjaro.

Eating smaller meals, avoiding foods that worsen symptoms and maintaining adequate hydration may help.

However, severe or persistent nausea, repeated vomiting or an inability to maintain fluid intake requires prompt medical advice.

Dehydration can cause serious complications, including kidney problems, particularly in older adults.

Don’t wait until you’ve been unable to drink for 24 hours before seeking help if you’re becoming dehydrated or significantly unwell.

Worries About Not Eating Enough

Many people worry they’re not eating enough when their appetite decreases.

This concern is particularly relevant for older adults, who need adequate protein, energy, vitamins and minerals to maintain muscle mass and overall health.

Focus on eating a varied, nutrient-rich diet that includes protein sources, vegetables, fruit and other foods appropriate to your health needs.

If you’re struggling to eat enough, losing weight unusually quickly or becoming weak or fatigued, contact your clinical team.

A dietitian may be able to help you maintain adequate nutrition while using weight loss injections.

Dizziness and Balance Problems

Dizziness can have several causes during weight loss treatment, including low blood glucose, changes in blood pressure or dehydration.

If you experience dizziness, sit or lie down to reduce your risk of falling.

Check your blood glucose if you have diabetes and have been advised to monitor it.

Seek medical advice if dizziness persists, recurs or is associated with other symptoms.

Dizziness can increase the risk of falls, so it’s particularly important to address this promptly in older adults.

Concerns About Muscle Loss

Worries about losing muscle alongside fat are justified.

Preserving muscle mass is particularly important for maintaining strength, mobility and independence.

Include appropriate protein sources throughout the day. However, protein requirements vary depending on factors including body weight, kidney function, nutritional status and other medical conditions.

Rather than following a fixed protein target, ask your clinician or dietitian what amount is appropriate for you.

Resistance exercises, including adapted strength training, can also help maintain muscle function.

For detailed strategies on protecting muscle mass during weight loss, see our guide on Protecting Muscle and Strength on Weight Loss Injections.

What Success Looks Like at One Month

Success at the one-month mark isn’t measured solely by the scales.

Tolerating the Medication Well

One important measure of progress is how well you’re tolerating the medication.

You may experience mild gastrointestinal symptoms, but persistent side effects that interfere with eating, drinking or daily activities should be discussed with your clinical team.

Maintaining adequate nutrition, hydration and physical function is particularly important for older adults.

Noticing Appetite Changes

By one month, some people notice changes in their appetite and relationship with food.

You might feel satisfied with smaller portions, experience fewer cravings or think about food less frequently.

However, these changes aren’t guaranteed during the first four weeks.

Your clinician will consider your overall response to treatment rather than relying solely on early appetite changes.

Improved Blood Sugar or Blood Pressure

If you have diabetes, you may notice changes in blood glucose readings during the first month.

Similarly, some people experience changes in blood pressure as treatment progresses.

These effects vary and should be monitored where clinically appropriate.

Any changes to existing diabetes or blood pressure medication should be made by the relevant healthcare professional.

Feeling More Confident About Treatment

By the end of your first month, you may feel more confident about the treatment process.

You’ve gained experience with injections, started recognising possible side effects and developed a better understanding of how treatment fits into your daily routine.

This growing confidence can help you engage with your weight loss programme and communicate effectively with your clinical team.

Preparing for Month Two and Beyond

As your first month ends, your clinician will review your progress and discuss the next stage of treatment.

Reviewing Your First Month

Your follow-up appointment may cover how you’ve tolerated the medication, whether you’ve experienced side effects and whether you’ve noticed changes in appetite or weight.

Your clinician may also review blood glucose, blood pressure or other measurements where relevant.

This is an opportunity to discuss any difficulties and ask questions about the next stage of your weight loss treatment.

Deciding on Dose Escalation

Under the usual UK dosing schedules, the next doses after four weeks are:

Wegovy: Increase from 0.25 mg to 0.5 mg once weekly.

Mounjaro: Increase from 2.5 mg to 5 mg once weekly.

However, dose escalation should follow the relevant UK Summary of Product Characteristics and your clinician’s assessment.

For Wegovy, delaying escalation or reducing to the previous dose may be considered if significant gastrointestinal symptoms occur.

For Mounjaro, dose increases follow the authorised schedule, with subsequent increases made in 2.5 mg increments after at least four weeks on the current dose where appropriate.

If you’re struggling with side effects, contact your clinician rather than changing your dose or continuing escalation independently.

What to Expect as Doses Increase

As your dose increases, you may notice more pronounced appetite suppression or additional weight loss.

Gastrointestinal side effects can also occur or worsen following dose increases.

Not everyone will experience these changes, and side effects aren’t necessarily milder at higher doses.

Your clinician will assess your response, tolerability and nutritional needs throughout treatment.

Continuing Good Habits

The habits you’ve established during your first month remain important as weight loss treatment continues.

Maintain a balanced diet, prioritise adequate protein intake, stay appropriately hydrated and continue physical activity suited to your ability.

These measures support weight loss while helping to preserve muscle strength and overall health.

When to Contact Your Medical Team

Understanding when to seek medical advice is important for safe treatment.

Urgent Concerns Requiring Same-Day Contact

Seek urgent medical assessment if you develop severe, persistent abdominal pain, particularly if it radiates to your back. This may be a sign of acute pancreatitis.

If pancreatitis is suspected, treatment should be stopped pending urgent assessment. If confirmed, the medicine should not be restarted.

Persistent vomiting, severe diarrhoea or signs of dehydration also require prompt medical advice.

If you have diabetes and experience hypoglycaemia, follow your prescribed hypo-treatment plan. Severe hypoglycaemia, particularly where someone becomes unconscious or cannot swallow safely, is a medical emergency.

Chest pain, severe breathing difficulties, collapse or sudden confusion require emergency medical assistance. Call 999 where appropriate.

Non-Urgent Concerns for Routine Contact

Mild nausea, occasional constipation or minor changes in bowel habits can be discussed with your clinical team, particularly if symptoms continue or become troublesome.

If you’re concerned about not eating enough, feeling unusually tired or experiencing other changes that worry you, seek advice rather than waiting for symptoms to worsen.

Building a Relationship with Your Medical Team

Your first month is about more than starting medication. It’s also about establishing communication with your clinical team.

At Bodyline, our specialised support for over-70s takes account of the additional considerations involved in weight loss treatment for older adults.

Don’t hesitate to ask questions, raise concerns or request clarification about anything you don’t understand.

Looking Ahead: Building on Your First Month’s Success

Your first month on weight loss injections provides a foundation for the months ahead.

You’ve begun learning how to manage the medication, recognise possible side effects and establish routines that support your treatment.

Remember that weight loss is rarely linear. Your progress may vary from week to week, and your clinician will assess your overall response over time.

Stay focused on the bigger picture. Weight loss may be one goal, but maintaining strength, mobility, independence and nutritional health is particularly important for people over seventy.

Continue prioritising adequate protein intake and suitable strength training as your weight loss progresses.

Stay connected with your medical team through regular appointments and monitoring. Your treatment needs may change over time, and ongoing communication allows appropriate adjustments.

If you’re considering weight loss injections after seventy, book a consultation to discuss whether treatment is suitable for your individual health needs.

You can visit one of our weight loss clinics throughout the North West or explore our online consultations.

With appropriate clinical assessment, ongoing support and attention to nutrition and physical function, weight loss treatment can form part of a personalised approach to improving health and wellbeing.