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Deer Supply & Research

Guide 03 · Injection day

Your First Injection

A calm walkthrough of day one: what is in the box, how the pen works, and every step in order. Ten quiet minutes is all it takes.

Hands preparing an unbranded injection pen at a bathroom counter
Injection day one: pen, fresh needle tip, alcohol swab

Before you start

It is easier than you are imagining

If the word injection is the thing standing between you and starting, you are in good company. Here is the honest picture: it is one small injection, once a week, with a pen designed for people who have never done this. The needle is finer than a sewing pin, and the whole thing is over in about ten seconds.

These medications are subcutaneous, which just means they go into the layer of fat right under the skin. Not into muscle, not into a vein. There is nothing to find and nothing to aim for; anywhere on the approved sites works.

Ask almost anyone who has done it and they will tell you the same thing: the anticipation was the hard part. The second week feels routine. By the fourth, it is just part of the calendar.

Unboxing

What comes in the box

Deer orders include the supplies you need to get started, so there is no separate pharmacy run before day one. Four things matter:

The pen

The device that holds your medication and dials out each dose. You will use the same pen week after week; only the needle tip changes.

Pen needle tips

Small single-use tips that twist onto the end of the pen. Each one is used once and then disposed of. The needle itself is finer than a sewing pin.

Alcohol swabs

For cleaning the patch of skin before you inject. One swab per injection is all it takes.

Instructions

The printed instructions for your pen, including how to attach a needle tip and how to prime it before the first use.

The walkthrough

Eight steps, in order

Set aside ten unhurried minutes the first time and go slowly. There is no step here that rewards speed.

  1. 01

    Wash your hands

    Plain soap and water. This is the whole prep for you; the pen does the rest.

  2. 02

    Check this week's dose

    Open your product page and find the dosing schedule. Every protocol steps up gradually, so the right dose depends on which week you are in. Confirm it before you dial anything.

  3. 03

    Attach a fresh needle tip

    Twist a new tip onto the pen. A fresh tip every time keeps the needle sharp and the injection close to painless.

  4. 04

    Prime the pen

    Follow the included instructions to prime. Priming just clears any air and confirms the pen is dispensing before it touches your skin.

  5. 05

    Swab a spot

    Pick a patch of skin on your stomach, at least 5 cm from the navel, or on the front of your thigh. Wipe it with an alcohol swab and let it dry for a few seconds.

  6. 06

    Pinch, insert, and hold

    Pinch the skin gently, insert the needle straight in at 90 degrees, press the button, and hold it there while you count slowly to 10. The count makes sure the full dose goes in.

  7. 07

    Dispose of the tip

    Twist the used tip off and drop it into a sharps container. Never into the regular trash, and never reuse a tip.

  8. 08

    Rotate sites next week

    Same routine every week, different spot. Move around the stomach or alternate thighs so no single patch of skin gets used twice in a row.

After day one

What the first weeks feel like

The injection itself is the easy part. The adjustment happens in your digestive system: nausea, constipation, or an unsettled stomach are the common early side effects. They tend to be most noticeable in the days after a dose increase and usually ease as your body adapts, which is exactly why every protocol starts low and steps up slowly.

If something feels wrong, or a side effect is severe or simply not easing, do not push through it alone: talk to a licensed healthcare professional. This guide is general research context, not medical advice, and it is no substitute for someone who knows your health history.

Next up: Titration, Explained, on why every protocol starts low and steps up.