Weight loss injections have become an extremely popular way to lose weight.  Professionals working with post-trauma clients, such as case managers and allied health professionals, often want to know if weight loss injections are an appropriate option for this client population.

Why post-trauma clients struggle with weight gain

Weight gain after a major trauma is hugely problematic for many clients after a brain injury, spinal cord injury, amputation or complex orthopaedic trauma.  These clients typically lose weight and muscle mass rapidly while in hospital, predominantly due to:

• high levels of systemic inflammation from their injuries (and associated catabolism).
• inactivity and muscle disuse (due to being bedbound for long periods of time, reduced mobility and restricted options for physical activity).
• muscle atrophy below the injury site (in the case of a spinal cord injury).
• poor food intake overall (due to being in a coma, nil by mouth for procedures or surgery, not liking the food in hospital and/or hospital food not being nutritionally adequate).
• an inadequate protein intake in hospital.

Someone’s overall muscle mass is a huge factor in determining their metabolic rate.  This means that post-trauma clients frequently have a slower metabolism after the acute phase of their injuries subside.  If clients then go back to their pre-injury eating habits (which many of them do), they will gain body fat and weight.  Intensive physiotherapy and/or strength training in the gym are needed to rebuild the lost muscle.

In addition to the above physiological changes that occur after a life-changing injury, there are many other factors that can make the risk of weight gain more likely in this population.  These include (but are not limited to):

• reduced mobility and/or reduced ability to engage in physical activity.
• pain, fatigue and/or low mood making meal preparation more difficult.
• support workers not having sufficient time, training or experience to prepare nutritious food for clients.
• medication-induced weight gain from commonly used medications, such as antiseizure medications, antidepressants and/or neuropathic pain medications.
• diminished mental capacity to understand the consequences of their food choices.
• impulsivity around food.
• difficulty planning and preparing food due to impaired executive function.

It’s therefore no surprise that many post-trauma clients are considering weight loss injections as a quick fix to this very complex problem.

Should weight loss injections/medication be considered in post-trauma clients?

Deciding whether weight loss injections are appropriate for a post-trauma client requires the entire multi-disciplinary team to weigh up both the benefits and risks.  While the key benefits relate to weight loss, improved blood glucose levels and improved cardiovascular markers, this needs to be weighed against the fact that this population already has a compromised nutritional status, muscle loss and bone loss.  The medication-induced changes to appetite, alongside the rapid and significant weight loss from weight loss injections, are likely to make these problems worse.

All of these benefits and risks are extensively outlined in our one-hour evidence-based webinar on “Weight Loss Injections after Major Trauma…appropriate or not?”

The latest research on weight regain

The newest research from the January 2026 British Medical Journal on “Weight regain after cessation of medication for weight management: systematic review and meta-analysis” adds additional information worth considering.

• Around 50% of people with obesity discontinue weight loss injections/medication within 12 months.

• After discontinuing any weight loss medication, the average rate of weight regain is 0.4kg/month, with an expected return to baseline weight in 1.7 years (on average).

• After discontinuing semaglutide or tirzepatide weight loss injections specifically, the average weight regain is 0.8kg/month, with an expected return to baseline weight within 1.5 years. This is regardless of whether any behavioural support was offered during or after the use of these injections and regardless of how much weight was lost during active treatment.

• After discontinuing a behavioural weight management program, the average weight regain is 0.1kg/month with an expected return to baseline weight within 3.9 years.  This means that weight regain after using any type of weight loss medication is significantly FASTER than weight regain after behavioural weight management programs.

• Any improvement in metabolic parameters experienced with the weight loss injections/medication, such as improved HbA1c, cholesterol levels and blood pressure, were predicted to return to baseline within 1.4 years. Conversely, after behavioural weight management programs, the benefits to these parameters lasted for about five years.

The take home message

When using non-pharmacological weight loss interventions (meaning behavioural interventions alongside dietary changes and physical activity) –> people don’t lose as much weight, but they keep it off longer and they regain it at a slower rate.

Compare this to pharmacological weight loss (e.g. weight loss injections/medication) –> where people lose more weight and do so quickly, but they also regain it faster.

Weight loss injections/medication should therefore not be considered for short-term use.  The decision to use weight loss injections/medication in the first place needs to be made very carefully, with significant consideration to the benefits, short-term risks and side effects of the medication itself and potential long-term risks associated with weight regain.  For example, when people lose weight, they lose both muscle mass and body fat and when they regain the weight, they tend to regain mostly body fat.  These changes to body composition are not without consequence.

The above information applies to weight regain in the general population.  There is very little research looking at the use of weight loss medication in clients after a major trauma, and no research that we are aware of that looks at weight regain in this population specifically.

For more information, please see our article on the “Cost effectiveness of weight loss injections.”

You are also welcome to watch the recording of our free one-hour webinar on “Weight Loss Injections after Major Trauma…appropriate or not?”  In this webinar, we discuss the latest research on weight loss injections and how the research applies to clients after a brain injury, spinal cord injury, amputation or complex orthopaedic trauma.

To discuss or refer a case management or litigation client who is currently taking or considering weight loss injections/medication, please contact Specialist Nutrition Rehab at info@specialistnutritionrehab.co.uk or 0121 384 7087.

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