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Between us, we realised that almost no provider — not even the NHS — was offering serious psychological support alongside the medication, and that this gap was causing real harm. So we wrote The Weight Loss Prescription to fill it. The book covers everything you need to know about GLP-1 medications: how they work, how to use them safely and effectively, how to manage side-effects, and how to come off them without regaining the weight. Alongside the medical guidance, it contains a detailed psychological programme, developed by Courtney, designed to be worked through while you are on the medication. The aim is to address the underlying issues that lead to obesity in the first place, so that when the time comes to stop the jabs, you have genuinely changed your relationship with food rather than simply been on a very expensive temporary diet.

What we have learnt is that these medications do something remarkable: they quieten what we call “food noise”, the relentless mental chatter around food that can consume hours of every day. For the first time, many patients describe a sense of peace around food that they have never known before. But that quiet is a window, not a cure. The emotional triggers, the habits built over decades, the relationship with food that was there long before the jab — none of that disappears on its own. Without addressing it, the medication is ultimately a temporary reprieve. The moment it stops, the food noise returns and the weight follows. That is why the psychological work is not an optional extra. It is, in our view, the whole point. Here are the questions that patients ask me time and time again.

Do you have to reach one of the higher doses to lose weight?

This is one of the most persistent myths I encounter. A significant number of people lose weight perfectly well without ever reaching the top dose. The titration schedule — where your dose is incrementally increased over weeks or months — exists to allow your body to adjust gradually and reduce side-effects, not because higher is always better. I advise patients to increase only if their current dose has genuinely stopped working: weigh yourself once a week, and if the weight has plateaued over several consecutive weeks, only then consider moving up. Daily weighing is counterproductive. Higher doses bring a greater risk of side-effects, and there is emerging evidence that racing to the maximum may cause the body to develop tolerance. Slow and steady, every time.

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Can you pause for events where you want to enjoy your food, like a wedding or a holiday?

Courtney and I call this pause the “Maldives mindset”. One of my patients had saved for years to go on an all-inclusive holiday and told me that he was planning to stop his medication for the fortnight to “get his money’s worth”. The resort had world-class diving and extraordinary scenery. The thing he was most focused on was the buffet. His relationship with food was still the problem, and the medication had not yet helped him address it. Beyond the psychological issue, stopping and restarting causes real physical problems: each restart means the body adjusts from scratch, making side-effects more likely to return. He eventually decided to stay on his medication throughout and came back having lost another 1.5kg (3lb). “I actually tasted things properly for the first time,” he said.

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How long does it typically take people to reach their target weight?

The time it takes to reach your weight-loss goal varies considerably, but someone losing weight at a safe, sustainable pace might expect 12 to 18 months if they have a significant amount to lose. The temptation is always to rush, and I actively discourage it. Rapid weight loss carries real risks, particularly muscle loss and, in post-menopausal women, reduced bone density. I had a patient who, against my advice, had been barely eating 600 calories a day. She was thrilled with her progress. But when she checked her body composition, she had lost far more muscle than fat: her body had essentially been cannibalising itself, slowing her metabolism and making keeping the weight off much harder. Slow and steady is not a consolation prize. It is genuinely the better approach.

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Once you’ve reached your target weight, can you stop taking it?

This is one of the most heartbreaking patterns I encounter. A patient I’ll call Susan had been on her medication for 14 months and lost 19kg (3st). She stopped the week she hit her target. Six months later she was back in touch having regained nearly 12.5kg (2st). What had gone wrong is rooted in “set point theory”: the idea that each body has a weight range it considers normal and will actively fight to maintain, using hunger hormones and metabolic adjustments to get back there. When someone has been significantly overweight for years, that set point shifts upwards. Stop too soon and the body fights its way back. Susan told me that within weeks of stopping, the pull of sweet and high-calorie foods felt as overwhelming as it always had. Reaching your target weight is not the finish line. It is closer to the halfway point.

How long should the maintenance dose period be?

After the active weight-loss phase, I advise patients to transition to a lower “maintenance dose” at which they neither gain nor lose weight, continuing pharmaceutical support while the psychological work consolidates. This allows the body’s set point to gradually accept the new weight as normal and gives the brain’s reward pathways time to recalibrate. I typically recommend about 12 months at maintenance dose after reaching target weight, meaning the full programme takes roughly two years. When I tell patients this, the reaction is often alarm. But most have spent a decade or more at war with their bodies. Two years to genuinely reset that relationship is, if anything, a bargain.

I’m not hungry at all on the jabs. Is it all right to skip meals completely? I’m only having one a day

Not eating enough is more dangerous than many people realise. Your body still needs nutrition even when it is not asking for it. Going most of the day without eating causes blood sugar instability, muscle breakdown and nutritional deficiencies. It is worth knowing that many of the side-effects people attribute to the medication itself — including constipation, fatigue, hair loss and headaches — are often the result of simply not eating regularly enough. The absence of hunger is not the absence of need. Aim for three modest meals a day, even if they are small, and think of eating as the foundation of the psychological work of building a healthier relationship with food.

Is it advisable to stay on a small dose for ever?

For some people, particularly those with significant obesity-related health conditions, staying on a low-maintenance dose long-term may be clinically appropriate, much as people stay on blood pressure medication indefinitely. However, my goal is always to equip people with the psychological tools to manage without pharmaceutical support. What I caution against is using a perpetual low dose as a substitute for doing that work. That is not treatment. It is dependency dressed up as management.

What’s the truth about the impact on the pancreas?

Very rarely, GLP-1 medications can cause pancreatitis, or inflammation of the pancreas. The symptoms are distinctive: severe, persistent abdominal pain that may radiate to the back, with nausea, vomiting and fever. This is quite different from the mild digestive discomfort many experience in the early weeks. If you develop severe abdominal pain that does not improve, seek medical attention promptly. For the vast majority of people, the pancreas is entirely unaffected and the health benefits considerably outweigh this rare risk.

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And the gallbladder?

Rapid weight loss, from any cause, increases the risk of gallstones. When weight is lost quickly, changes in bile composition can cause crystals to form. Know the symptoms: severe abdominal pain, particularly after fatty foods, sometimes with nausea. People with existing gallstones are typically not prescribed these medications, and it is another reason to lose weight slowly.

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Should I focus on fibre or protein? The advice seems to be changing.

Both protein and fibre matter, and you should not be choosing between them. Protein is essential to protect muscle mass: aim for a good source at every meal, whether it’s eggs, fish, chicken, pulses or Greek yoghurt. Fibre slows digestion, helps you feel fuller, feeds the gut microbiome and significantly helps with constipation. One of the most common mistakes I see is people eating smaller portions of whatever they ate before. If that food was not particularly nourishing, eating less of it is not good enough. Many people who struggle with their weight have developed a habit of using food to manage feelings, reaching for certain foods not because they are hungry but because of stress or anxiety. As Courtney and I discuss in the book, what you put in your mouth very often has its origins in your mind. These medications offer a genuine opportunity not just to change why you eat but what you eat.

I’ve got a big birthday this summer. Can I speed up getting onto the higher doses?

No, for your own sake. The titration schedule is physiologically necessary, not bureaucratic caution. Rushing it dramatically increases the risk of severe nausea and vomiting that can make the medication intolerable. I have known patients who pushed too fast, felt consistently wretched and abandoned the medication altogether. If you want to look and feel your best by summer, the counterintuitive answer is to take it slowly.

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Where’s the harm in ordering the dose I want online without seeing a doctor?

I see the consequences of this in my NHS work regularly. One patient had been quietly buying his medication from an online pharmacy that had asked him to fill in a brief questionnaire and nothing more. He was also taking sulphonylureas, a type of diabetes medication that stimulates insulin production, lowering his blood sugar level. As he lost weight and his blood sugar improved, his existing medication began causing it to drop dangerously low, a condition called hypoglycaemia, with symptoms including dizziness, confusion and sweating. Nobody had reviewed his medication list. He had no idea what was happening. These are serious prescription medications that interact with other drugs and require monitoring as your weight and health change. The slightly lower price of an unregulated provider is not a saving. It is a gamble.

What’s the best way to prep to go on the jabs? Is it OK to have a blowout before my first dose?

The impulse is understandable: the sense that you are about to be deprived, so you had better enjoy it while you can. My advice is to resist it, not because a last supper is physically dangerous but because of what it reveals about your mindset going in. If your first act is to binge before the medication kicks in, you are already framing the jab as a restriction rather than a tool. The most useful preparation is psychological: noticing your patterns around food, what triggers you to eat when you are not hungry and what emotions you have been managing with food. That is the work the medication creates space for, and it is what The Weight Loss Prescription was written to guide people through.

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Does it make any difference where I inject? I heard injecting in your stomach can reduce side-effects

There is anecdotal talk online about this, but no robust clinical evidence to support it. You can inject into the upper arm, the abdomen (at least 3 to 5cm from the belly button), or the front of the thighs. Most people find the abdomen easiest. What does matter is rotating the site by at least 3cm each time to avoid scar tissue and injection site reactions, which affects absorption. Inject at a 90-degree angle and withdraw straight out to reduce bruising.

Does it matter if I only eat 500 calories a day? Should I try to eat more?

I do not advise obsessively counting calories, but if you are concerned that you are barely eating, it is worth ensuring you reach at least 1,200 calories a day for women and 1,500 for men — the minimum most clinicians would consider safe. Consistently eating far below this risks severe muscle loss, nutritional deficiencies, fatigue and hair shedding. Smaller and more frequent meals often help if appetite is very low.

What should I make sure I eat or avoid?

Prioritise protein at every meal and eat plenty of vegetables. Good healthy fats, oily fish, avocado, nuts and olive oil matter too. Reduce ultra-processed foods, refined carbohydrates and high-sugar items, not just because they are calorie-dense but because they perpetuate the reward pathways the medication is giving you a window to reset. With alcohol, many people find they become noticeably less interested in drinking on these medications, which makes biological sense: GLP-1 drugs act on the same reward pathways that alcohol works on. That is no bad thing. But alcohol also destabilises blood sugar levels, which matters particularly when you are eating less than usual. If you do drink, do so cautiously.

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A year later, the weight is creeping back on. Can a month back on the jabs every so often help?

Intermittent use is essentially yo-yo dieting with a needle rather than a diet book, and the well-established problems with yo-yo dieting apply here too: repeated cycles of loss and regain are demoralising, can accelerate muscle loss and may make the body increasingly resistant to change over time. On-off courses suppress appetite temporarily, but when you come off again the food noise returns and the same habits reassert themselves. The more useful question is not “How do I get back on the medication?” but “What has changed in my relationship with food?” That deserves a psychological answer. Revisiting the psychological work that should have accompanied the medication in the first place will serve you far better than intermittent jabs.

Will they affect my sleep?

For many people, the jabs have a positive impact on sleep. Sleep apnoea is strongly linked to excess weight and there is good evidence that weight loss on these medications can reduce its severity, with better sleep quality following. Some people report vivid dreams in the early weeks, which usually settles.

Can they affect my mood?

When these medications first became widely used, there was genuine clinical concern that they might worsen mood or trigger depression, the worry being that dampening the brain’s reward pathways might leave people feeling flat or empty. We are now increasingly confident that this is not what happens. That said, some people find that as the food noise diminishes, emotions that had long been managed with food begin to surface: anxiety, low mood, unresolved grief. This is not a side-effect of the medication. It is an invitation to do the psychological work and it is important not to ignore it. If you notice significant or persistent low mood or anxiety on these medications, please speak to your GP or a psychologist.

Is ‘Ozempic face’ avoidable?

Rapid weight loss can leave loose skin where significant fat has been lost, which is one of many reasons to lose weight slowly. You may also notice what has become known as “Ozempic face”: a hollowing or gauntness as fat is lost from the face. This can be alarming. The reassuring news is that for many people the body gradually redistributes fat over time, and the face tends to fill out somewhat as things settle. There is also an adjustment period, for the person themselves and those around them, in simply getting used to a slimmer face. Most people do come to see it as just part of who they are now. A skin, hair and nails supplement is sensible throughout.

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Will I lose hair?

Some people experience increased shedding, and it can be distressing. It is almost certainly not a direct effect of the medication itself, but of rapid weight loss, which can trigger a temporary phase called telogen effluvium. The same thing occurs after bariatric surgery. It typically stabilises as weight loss plateaus and resolves over several months. Losing weight more slowly reduces the risk, as do adequate protein intake and a hair supplement.

Can I use the jabs to cut smoking or drinking?

This is one of the most fascinating areas of emerging research. GLP-1 receptors are found in the brain’s reward centres, and there is growing evidence that the medications can reduce the pull of addictive behaviours beyond food. I hear this anecdotally regularly: one patient had barely touched alcohol since starting despite previously drinking most evenings, another said the desire for cocaine had simply gone, a third reported that a longstanding problem with gambling had resolved. These medications are not licensed for addiction treatment and we cannot make therapeutic claims, but the biological plausibility is compelling and clinical trials are under way.

What’s the best approach to exercise when on the jabs?

Weights, without question, are the focus, but cardiovascular exercise definitely has a role. When the body is in calorie deficit it tends to break down muscle for energy. From the age of 30 we already lose between 3 and 8 per cent of our muscle mass per decade, and rapid weight loss accelerates this considerably. Resistance training builds and protects muscle, raises the metabolic rate and improves body composition in ways that cardio alone cannot. Aim for two to three sessions a week alongside some cardiovascular exercise. If you have never lifted weights before, a few sessions with a trainer to establish good technique is well worth the investment.

For more information, worksheets and a downloadable weight-tracker, go to theweightlossprescription.com

The Weight Loss Prescription by Dr Max Pemberton & Dr Courtney Raspin (HarperCollins £16.99). To order a copy go to timesbookshop.co.uk. Free UK standard P&P on orders over £25. Special discount available for Times+ members