In a September 2026 YouTube Short, US urologist Dr Alex Tatem shows how he prepares a week of his own daily testosterone injections in about ten minutes. He draws once with a 3ml syringe, then fills seven 1ml insulin syringes through the open back of the barrel, a technique he calls "back loading". This guide covers his setup, how our syringes compare, and the risks of the method. For general technique, see our Subcutaneous Testosterone Injection Guide (subcutaneous, or SubQ, means under the skin), or browse our injection supplies collection.

Seven capped 1ml 31G 6mm insulin syringes in a row above a 10ml draw syringe with a pink-hub 18G needle and two alcohol pad sachets on a grey bench
A week of supplies for Dr Tatem's setup: seven 1ml insulin syringes, one per day, plus a draw syringe. Shown with our 1ml 31G 6mm insulin syringes, 10ml draw syringe and alcohol wipes; his video uses 30G half-inch syringes and a 3ml syringe with a 23G needle. Illustrative photo.

Dr Tatem's daily routine

Source: Why I Inject Testosterone EVERY DAY (Dr Alex Tatem, YouTube Short, 19 September 2026).

Dr Tatem contrasts the package insert, which he says calls for one deep injection into the buttock every two to four weeks, with his own prescription: an injection into the thigh every morning. He says testosterone "hangs around for about eight days", so one big shot, even once a week, "turns your life into a roller coaster", while daily injections are "where that roller coaster flatlines". How long testosterone lasts depends on the product (the ester and formulation). Each morning's injection, he says, is "a tiny poke in the quad" that takes about 10 seconds.

He doesn't say whether his injection is subcutaneous or intramuscular (into the muscle). In our experience, a half-inch (12.7mm) needle in the thigh, where many men carry little fat, is likely to reach the muscle, making his injection intramuscular. Our team has found the 31G 6mm insulin syringe works well for this kind of daily setup.

What Vigorous Steve says about SubQ

Vigorous Steve is a bodybuilding and TRT YouTuber, not a medical doctor. In Subcutaneous (SubQ) Vs Intramuscular (IM) | Does It Actually Make A Difference? (April 2026), he points out that most research on oil-based injections looks at intramuscular use and there is little clinical evidence on subcutaneous use, so his view rests on 20 years of his own experience and what he has seen in clients and other bodybuilders. He says testosterone levels from a subcutaneous injection rise a little more slowly than from an intramuscular one but stay more stable, with smaller peaks and valleys.

The equipment in his setup

For a week of prep, Dr Tatem uses the following. Our syringes differ from his in a few ways; see our supplies for this setup.

  • Seven 1ml (1cc) insulin syringes with fixed 30G half-inch (12.7mm) needles, "the same needle people use for insulin", one per day. Each is sterile and single-use. Half an inch is longer than the 4mm to 8mm needles commonly used for SubQ injections.
  • One 3ml syringe with a 23G needle, only for drawing from the vial and transferring the oil. He injects with the insulin syringe.
  • A plastic test-tube rack to hold the insulin syringes upright while he fills them.
  • A jar to keep the finished syringes together.
  • His testosterone vial.

Not shown in the Short, but part of any home injection routine: alcohol wipes for the vial stopper and skin, and a sharps container for the used draw needle and each daily syringe.

About the insulin syringe scale. A 1ml U-100 insulin syringe is marked from 0 to 100 units, where 100 units = 1ml (1 unit = 0.01ml). Syringe units are not milligrams of testosterone.

The risks of back-loading

Back-loading means taking the plunger out of a sterile single-use syringe and filling the barrel from the back. Syringes aren't designed to be used this way: it exposes the inside of the barrel and the plunger's rubber stopper to air and handling. The standard approach is to draw each dose just before you inject it. The main risks with Dr Tatem's method:

  • Contamination. Wash your hands, use a clean surface, wipe the vial stopper, and don't touch the inside of the barrel, the rubber stopper or the needle. This lowers the risk but doesn't remove it.
  • Storage is unproven. We are not aware of validated data on storing oil in insulin syringes for days, and pre-filling syringes is not an approved use of these products. The rubber stopper hasn't been shown to be compatible with prolonged oil contact, the product's labelled storage assumes the original vial, and oil can crystallise in the cold.
  • Dose accuracy is harder to confirm. Dripping oil into an open barrel is not a measured draw, and some oil can be pushed out with the air. Check the volume on each syringe's 0 to 100 unit scale once the plunger is back in and the air is out. The markings on a larger draw syringe are too coarse for small volumes.
  • Inject with the insulin syringe only. The draw needle (23G in Dr Tatem's setup, 18G on our draw syringe) is for drawing and transferring oil, never for injecting.
  • Never re-use a syringe or needle, and never put a used needle back into the vial.

How he back-loads a week of syringes

Dr Tatem describes five steps.

Step 1: Plungers out

The insulin syringes stand in the rack with their needle caps on, and "every plunger comes out the back". His reason: "you can't pull oil through a needle this thin. You'd be there till lunchtime." Thick oil is slow to draw through a fine insulin needle, so the oil goes in through the open back of the barrel instead. Back-loading only solves the draw: thick oil can still be slow to push out through a fine needle when you inject.

Step 2: One draw with the 3ml syringe

With the 3ml syringe and 23G needle, he draws from the vial once: "One pull and that's a whole week and a half." The wider 23G needle lets thick oil flow far more easily than a 30G insulin needle.

Gloved hands drawing golden oil from a vial into a 10ml draw syringe with a pink-hub 18G needle
Step 2: one draw from the vial. Shown with our 10ml draw syringe and 18G needle; Dr Tatem uses a 3ml syringe with a 23G needle.

Step 3: Back-load each insulin syringe

Next he fills each syringe: "I then go down the row and drip one day into the back of each one. That's called back loading." He doesn't give his daily dose in the video.

A 10ml draw syringe with a pink-hub 18G needle dripping oil into the open back of one of seven capped 1ml insulin syringes standing in a rack, their plungers and end caps removed and laid on the bench
Step 3: back-loading. Seven capped insulin syringes stand in a rack with their plungers and end caps off, and oil is dripped into the open back of each. Shown with our 10ml draw syringe and 1ml 31G 6mm insulin syringes.

Step 4: Plungers in, air out, caps on

"Plungers go back in, the air goes out, and the caps go back on." Pushing the air out means taking the needle cap off and then recapping, which exposes the sterile needle and can leave an oil-coated tip capped for days. Recapping is also when needlestick injuries tend to happen.

Step 5: Into a jar

The finished syringes go into a jar. He says the whole prep "takes 10 minutes tops and I'm done for a week", and each morning is then a 10-second injection.

Seven capped 1ml insulin syringes pre-filled with oil, plungers back in, standing cap-down in an open glass jar with its metal lid beside it
Steps 4 and 5: plungers back in, air out, needle caps on, then into a jar. Shown with our 1ml 31G 6mm insulin syringes.

Disposal

After prep, the draw syringe and its needle go straight into a sharps container, and each insulin syringe goes in straight after that day's injection. Never put sharps in household rubbish or recycling. Take full containers to a participating pharmacy or council sharps drop-off point; see our Syringe Disposal Guide.

Gloved hand lowering a used 1ml insulin syringe needle-first into an open SharpSafe 1.8L sharps container on a bathroom vanity
Each used syringe and needle goes straight into a sharps container. Shown with our SharpSafe 1.8L sharps container.

Frequently asked questions

Why does Dr Tatem inject testosterone every day?

His own prescription calls for an injection into the thigh every morning. He says testosterone "hangs around for about eight days" and that one big shot, even once a week, "turns your life into a roller coaster". How long testosterone lasts depends on the product.

Why not just draw each day's dose with the insulin syringe?

Testosterone injections are usually oil-based, and thick oil is slow to draw through a fine 30G needle. As Dr Tatem puts it, "You'd be there till lunchtime." Drawing once with a wider 23G needle and back-loading gets around that, but drawing each dose directly with the syringe you inject with is how the syringe is designed to be used.

Is it safe to prepare a week of syringes in advance?

It hasn't been shown to be safe, so don't assume it is. It depends on the product, how clean the prep is and how the syringes are stored; see the risks of back-loading above.

What size syringes and needles does he use?

Seven 1ml (1cc) insulin syringes with 30G half-inch (12.7mm) needles for the daily injections, plus one 3ml syringe with a 23G needle for drawing. Our range has 1ml insulin syringes with a finer, much shorter 31G 6mm needle, and a 10ml draw syringe with an 18G needle.

Where do used syringes and needles go?

Straight into an approved sharps container, never household rubbish or recycling. See our Syringe Disposal Guide.

When to seek help

  • Redness, warmth, swelling, pus, fever or worsening pain after an injection: see a doctor
  • Oil that is cloudy, crystallised, discoloured or contains particles, or is past its expiry or beyond-use date: don't use it
  • Signs of a severe allergic reaction, such as swelling of the face or throat or difficulty breathing: call 000 immediately

Our supplies for this kind of setup

These are the Injection Supplies products that match the equipment in Dr Tatem's video, and how they differ from it.

Related guides: SubQ testosterone injection guide, needle and syringe size for TRT, how to read an insulin syringe, units to ml.