Wegovy is semaglutide, taken as an injection once a week, and licensed for weight management. The first week is mostly a week of gathering information, not a week to judge by results — there usually isn't enough time for a clear pattern to appear yet, and this page will not suggest what pace of change to expect or what a 'typical' first week looks like, because there isn't one that applies generally.

What the first week is good for is building an accurate starting record: what actually happened, in what order, and how you felt at each point. That record becomes useful later, especially at a first review appointment, where 'I think it was fine' is much less helpful to a prescriber than a few dated, specific notes covering the days in between.

Logistics worth writing down

  • The exact day and approximate time you had your first injection
  • Which site you used, in general terms, without needing to be precise
  • Where you are storing your pen, and any questions you had about the instructions in the leaflet
  • Any part of the process that felt unclear, so you can ask about it at your next contact with a pharmacist or prescriber rather than guessing
  • Whether you had any support or teaching from a pharmacist or nurse, and what was covered

Body-related notes worth writing down

  • Appetite: did it feel different, and at what point in the week you first noticed
  • Digestion: any nausea, fullness, constipation, or looser stools, and roughly when each started and settled
  • Sleep and energy: any noticeable change either way, even if you are not sure it is related
  • Injection site: any redness, swelling, or soreness, and how long it lasted
  • Mood or general wellbeing, in a sentence or two each day
  • Hydration: whether you were able to eat and drink as usual, particularly on days with digestive symptoms

None of this needs to be exhaustive. A few honest lines each day, or even every other day, is enough to be useful later, and it is far easier to keep up a short daily note than to try to reconstruct a whole week from memory afterwards.

Why this matters for your first review

A first review appointment tends to go better with specifics. 'Some nausea on days two and three, better by day five' tells a prescriber far more than 'I felt a bit off.' It also gives you something concrete to compare against in future weeks, rather than relying on a general impression that can shift with mood or memory, and it gives your prescriber a genuine baseline rather than a reconstructed one.

When something needs attention now

If you experience severe abdominal pain, repeated vomiting, an inability to keep fluids down, signs of a severe allergic reaction, or any symptom that feels seriously wrong, contact a healthcare professional promptly rather than waiting to mention it at a routine appointment. The first week is for noticing and recording, not for pushing through something that needs attention right now — a note in a log is not a substitute for care when something feels genuinely wrong.

Setting up the habit for the weeks ahead

However you choose to record your first week — a notes app, a paper diary, or a simple spreadsheet — try to use the same format you intend to keep using afterwards. Starting with one system and switching to another a few weeks in makes early comparisons harder than they need to be, and the first week's notes are often the ones people refer back to most, precisely because they capture a starting point nothing since has quite matched.

A short daily entry does not need to take more than a minute or two. The value comes from consistency and honesty, not length. If a day felt entirely unremarkable, writing 'no change today' is still useful information, because it tells you and your prescriber that nothing new happened, rather than leaving a gap you might later misread as something forgotten. Even a handful of words per day, kept up consistently, will usually be worth more at review time than a single detailed paragraph written from memory the night before your appointment.