What’s the difference in administration between Wegovy and other weight loss drugs?

Wegovy is taken once weekly via an injection pen, with doses stepped up over 16 weeks. Saxenda requires a daily injection, Mounjaro is a weekly injection like Wegovy, Mysimba is an oral tablet taken daily, and Orlistat is a capsule taken with each main fat-containing meal.

Why administration matters

How a medicine is taken often shapes whether people stick with it. For weight-loss treatments, convenience, ease of use, and side-effect management are just as important as effectiveness. The NHS and NICE both highlight that adherence is key: a drug can only work if it is taken regularly and correctly. That’s why the administration of Wegovy and other weight-loss medicines is worth comparing.

Wegovy: once a week, step by step

Wegovy (semaglutide) is given as a once-weekly injection using a pre-filled pen. People start at a low dose and gradually increase over 16 weeks until they reach the full 2.4 mg dose. This gradual “titration” helps reduce side effects like nausea and diarrhoea, which are common early on. The weekly schedule means fewer injections overall, which many people find easier to manage than daily dosing.

Saxenda: daily injections

Saxenda (liraglutide), another GLP-1 receptor agonist, is taken as a daily injection. Like Wegovy, it requires dose escalation, but the need to inject every day can be a drawback for some. Clinical trials showed it produced average weight losses of around 6–8% over a year, but its less convenient schedule and lower effectiveness compared to Wegovy have limited its long-term uptake on the NHS.

Mounjaro: weekly injections like Wegovy

Mounjaro (tirzepatide) is administered once a week, similar to Wegovy. It also uses a step-up dosing approach, moving gradually from 2.5 mg to higher maintenance doses, depending on treatment goals. In the SURMOUNT trials, tirzepatide achieved average weight losses of over 20% at higher doses, though it is currently licensed in the UK for type 2 diabetes, with NICE still reviewing its role in obesity treatment.

Mysimba: oral tablets

Mysimba (known internationally as Contrave) works very differently. It is a tablet that combines naltrexone and bupropion. The dose is increased over several weeks until it reaches two tablets twice daily. Some people prefer tablets over injections, but the frequency of dosing and side effects such as nausea, insomnia, or headaches can make adherence challenging.

Orlistat: with every fat-containing meal

Orlistat, one of the older weight-loss medicines, is taken as a capsule with each main meal that contains fat — typically three times a day. It works by reducing the absorption of dietary fat in the gut. While convenient in pill form, its effectiveness is modest, and side effects such as oily stools or urgency can discourage long-term use.

Why choice depends on lifestyle

The differences in administration matter for everyday life. Someone who struggles with remembering daily medicines may prefer a weekly injection like Wegovy or Mounjaro. Others may dislike injections altogether and prefer oral options, even if those require more frequent dosing. NHS guidance always emphasises tailoring treatment not just to medical need but also to personal preference and likelihood of adherence.

The full perspective

Weight-loss medicines vary not just in effectiveness, but in how they fit into daily routines. Wegovy offers weekly dosing with strong evidence for weight loss, Saxenda requires daily injections, Mounjaro is weekly but newer to the UK market, Mysimba involves multiple daily tablets, and Orlistat is tied to each meal. Understanding these differences helps patients and clinicians choose the treatment that is both effective and practical to continue long term.