Firstly, this is a 1ml clear plastic barrel syringe with a Luer Lock connector at the tip. So a separate needle screws on firmly and cannot pop off under pressure. In particular, the barrel carries clear graduations at every 0.01ml, which lets you measure small hormone doses accurately. Furthermore, the smooth white plunger runs cleanly for controlled dose measurement.
Luer Lock vs Luer Slip: the difference
There are two common needle-connection types on 1ml syringes:
Luer Lock (this product): the needle screws onto the syringe with a threaded collar. So it locks firmly and cannot pop off under pressure.
Luer Slip: the needle pushes on with a friction fit. So it can be quicker to attach, but it can also pop off under high pressure (for instance, when injecting a thick oil).
For thick oil-based hormone injections, Luer Lock is safer. So most TRT and HRT protocols use Luer Lock syringes for this reason.
Why the detachable design matters
A fixed-needle syringe (such as the Unisharp 29G 12mm) is fine for insulin or water-thin medicines. However, oil-based hormones (testosterone in grapeseed or sesame oil, some oestrogen preparations) are viscous. So drawing them through a fine needle is slow and can strip the needle sharpness. Furthermore, using a fresh, fine needle to inject after drawing means less pain and less trauma to the injection site. As a result, the two-needle draw-and-inject method is standard for oil-based injections, and needs a detachable syringe like Unifix.
Key features and details
Barrel volume: 1ml.
Graduations: 0.01ml (100 marks across the barrel).
Connector: Luer Lock (screw-on detachable).
Needle included: NO. Order needles separately to match your medicine.
Compatibility: fits all standard Luer Lock needles, including low dead space needles.
Plunger: white plunger with smooth rubber seal.
Sterility: individually blister-packed, sterile until opened.
Regulatory: CE-marked, single-use medical device.
Pack sizes: typically available as boxes of 100 or larger.
Storage: at room temperature, in the original box.
Disposal: use a 1-litre yellow sharps bin (available separately).
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Unifix 1ml Luer Lock syringe, a detachable-needle syringe for flexible self-injection
The Unifix 1ml Luer Lock syringe is a sterile, single-use, 1ml plastic barrel syringe with a Luer Lock connector for a detachable needle. So the needle screws firmly onto the syringe, unlike a Luer Slip syringe where the needle just pushes on. In particular, the detachable design lets you use a thicker needle to draw a viscous medicine and a finer needle to inject. Furthermore, this makes Unifix a common choice for oil-based hormone injections (TRT and HRT), fertility protocols, and other self-injection where flexibility matters. As a result, this is a workhorse product in UK pharmacy self-injection supplies.
When to see your prescriber before using this syringe
This is a medical device, not a treatment on its own. So some situations need proper professional input before you start using a Luer Lock syringe:
If you have not been shown how to give the injection by a nurse, pharmacist, or doctor.
If you are not sure which needle to screw on for drawing, or which needle for injecting.
If you have a bleeding disorder or are on blood-thinning medicines (warfarin, DOACs, dual antiplatelets).
If the injection site becomes red, swollen, hot, or painful (possible infection).
If you get a lump, hard patch, or dimple that does not settle at your injection sites.
If you cannot arrange safe sharps disposal.
If a child or non-consenting adult may have access to the syringes or needles.
If you have had a needle-stick injury or an accidental self-injection with the wrong dose.
For any needle-stick injury, contact NHS 111 or occupational health. In particular, do not delay if the syringe carried a medicine that could cause harm at the wrong dose (testosterone, oestrogen, or any prescription hormone).
Five key takeaways about the Unifix 1ml Luer Lock syringe
The Unifix 1ml Luer Lock syringe is a sterile, single-use medical device with a 1ml barrel and 0.01ml graduations.
The Luer Lock connector fits all standard detachable Luer Lock needles. So you choose the needle size to match your medicine.
Needles are NOT included. So order them separately (typically a wide-gauge draw needle plus a fine-gauge inject needle).
Each syringe is individually blister-packed for sterility. Never reuse a syringe.
Sharps disposal is the user’s responsibility. So a 1-litre yellow sharps bin (available separately) is the standard UK home option.
Why choose Courier Pharmacy for your Unifix syringes
Registered, independent, and patient-led
Courier Pharmacy is a UK-registered independent pharmacy regulated by the General Pharmaceutical Council (GPhC 9010051). So when you buy Unifix syringes through us, you get a proper pharmacy team, not a warehouse. Furthermore, our independence means we can take time on injection questions where a large chain often cannot.
Prescriber-led injection support
At Courier Pharmacy, we take injection safety seriously. In particular, our Superintendent Pharmacist Shazlee Ahsan is an Independent Prescriber with a special interest in endocrinology. So if you are a TRT or HRT patient and are not sure which draw needle and which inject needle to pair with your Unifix syringes, we can help you decide.
Dr Ada Jex-Cori, our brand pharmacist
Our brand pharmacist is Dr Ada Jex-Cori. She represents the spirit of what we do. Named for Ada Lovelace, Sophia Jex-Blake, and Gerty Cori, she stands for evidence-led, unafraid-of-questions medicine. Her message runs through everything we advise:
You’re not broken. The system is. We’re here to change that.
For anyone new to self-injection, this matters. So we treat injection questions as normal, not embarrassing.
Coordinated advice with your other supplies
If you take prescribed injectable hormones (testosterone, oestrogen, progesterone) or other injectable medicines, we can help you match the syringe to the medicine, and the needles to your injection route. So the syringe advice comes with proper context, not just a product sale. Furthermore, we can help you plan sharps disposal from the outset.
Care that keeps showing up
Self-injection is often a long-term routine. So we’re here for the follow-up questions along the way: swapping to a thicker draw needle if your current one is slow, moving to a shorter inject needle if you develop lumps, or discussing rotation patterns to protect your skin.
Buy Unifix 1ml Luer Lock Syringes from Courier Pharmacy
Unifix 1ml Luer Lock syringes are a medical device, available without prescription at courierpharmacy.co.uk. So supply is straightforward. Furthermore, our pharmacy team still reviews every sale as part of our routine check.
The four steps
Add Unifix 1ml Luer Lock Syringes in your chosen pack size to your basket.
Our pharmacy team reviews the sale as part of our routine check.
Your order dispatches promptly.
Follow your prescriber’s injection instructions. Contact us if you have questions.
If this syringe isn’t right for you
If our team thinks a different product fits your situation better, we’ll explain why and suggest the next best option. So this might mean:
A Unisharp fixed-needle syringe if you only ever inject one water-thin medicine and don’t need to swap needles.
A larger 2ml or 3ml Luer Lock syringe if your regular dose is over 1ml.
A specific pairing of draw and inject needles to go with your Unifix syringes.
A pen device if your medicine comes in a cartridge (many modern insulins and some hormones).
A 1-litre yellow sharps bin if you don’t already have safe disposal.
Referral back to your prescriber if you are not confident about injection technique.
Above all, we won’t sell you a syringe that isn’t right for your medicine. In short, honest guidance matters more than making the sale.
Materials and components of the Unifix 1ml Luer Lock syringe
A syringe is a medical device, not a medicine, so it has no active pharmaceutical ingredient. However, the materials and components matter because they determine sterility, compatibility with your medicine, and how the syringe feels in use. In particular, the Unifix 1ml Luer Lock syringe is manufactured to ISO 7886-1 for sterile single-use hypodermic syringes and uses an ISO 80369-7 compliant Luer Lock connector.
The barrel
The barrel is made of medical-grade polypropylene. So it is transparent for clear reading of graduation marks, chemically inert for most parenteral medicines, and shatter-resistant. In particular, the 0.01ml graduations are printed in high-contrast ink so small doses are easier to read. Furthermore, the barrel includes a finger flange at the top so you can brace two fingers against it while the thumb drives the plunger.
The plunger
The plunger is a polyethylene or polypropylene rod with a rubber plunger seal at the tip. So the seal is siliconised to let it move smoothly along the barrel wall without juddering. In particular, this smooth action matters when drawing up oil-based medicines slowly or injecting a precise small-volume dose. Furthermore, the plunger includes a stop that prevents it from being withdrawn fully out of the barrel.
The Luer Lock tip
The tip is a 6 percent Luer taper with an external thread, compliant with ISO 80369-7. So any standard Luer Lock needle screws onto this thread and locks in place with a quarter-turn. In particular, this positive lock stops the needle from popping off during a thick-fluid injection or when back-pressure rises. Furthermore, the Luer taper itself creates a leak-proof seal independent of the thread, so the connection stays fluid-tight even at injection pressures.
What the syringe does NOT contain
No latex (the syringe is latex-free).
No PVC in the barrel or plunger.
No DEHP or other phthalates.
No needle (needles are purchased separately).
No active pharmaceutical ingredient; this is a sterile empty syringe.
Sterility and pack
Each Unifix syringe is supplied sterile in an individually sealed peel-pouch and is for single use only. So the sterility expiry date is printed on the pouch and on the outer carton. In particular, if the peel-pouch is torn, opened, or shows signs of damage, discard the syringe and use a fresh one. Furthermore, do not re-sterilise or re-use.
What is the Unifix 1ml Luer Lock syringe for?
The Unifix 1ml Luer Lock syringe is used for self-injection of small-volume medicines where a detachable needle matters. So it is used in several common home-injection situations:
Testosterone replacement therapy (TRT)
Many TRT patients inject oil-based testosterone (Sustanon, Nebido, testosterone enanthate or cypionate). So these medicines are viscous, and drawing them into a fine needle is slow. In particular, the draw-and-inject method with a Luer Lock syringe like Unifix is standard practice. Furthermore, our Superintendent Pharmacist has an endocrinology background, so if you're unsure about needle pairing for your specific TRT formulation, ask our team.
HRT for the menopause or gender-affirming care
Some HRT protocols use oil-based oestrogen (oestradiol valerate) or progesterone by IM or SC injection. So a Luer Lock syringe with matched needles is the standard setup. In particular, some gender-affirming care protocols also use oil-based testosterone or oestrogen at home.
Fertility treatment
Some IVF and fertility protocols involve daily injections at home. So a Luer Lock syringe with matched needles is often supplied or specified by the fertility clinic. However, always use the syringes and needles your clinic specifies for your protocol.
Vitamin B12 injections
Hydroxocobalamin or cyanocobalamin injections are used for B12 deficiency and pernicious anaemia. So B12 is water-based, and a fixed-needle syringe (such as a Unisharp 29G) usually works well. However, some prescribers use a Luer Lock setup for B12, particularly if the patient prefers a specific inject needle.
Veterinary self-injection at home
Some pet owners give home injections to a pet under vet direction (for instance, insulin for a diabetic cat or dog). So the Luer Lock design is a common choice here too.
Where this syringe is not the right choice
However, some situations need a different product:
You only inject one water-thin medicine (such as insulin) and never need to swap needles. So a fixed-needle syringe (Unisharp) is simpler.
Your regular dose is more than 1ml. Use a 2ml or 3ml Luer Lock syringe instead.
Your medicine comes in a pen or auto-injector device. Use the manufacturer's cartridges and needles.
You have not been trained in the two-needle draw-and-inject technique.
How does the Unifix 1ml Luer Lock syringe work?
A syringe works on the basic physics of a piston inside a cylinder. So pulling the plunger back creates a partial vacuum inside the barrel, drawing fluid in through the attached needle. In particular, pushing the plunger forward displaces the fluid back out through the needle at a rate the user controls. Furthermore, several design features make this straightforward principle safe and precise for self-injection at home.
Pressure, vacuum, and fluid displacement
When you pull the plunger back, the volume inside the barrel increases while the fluid in the vial is at atmospheric pressure. So the pressure difference pushes fluid up the needle and into the barrel until pressures equalise. In particular, this is why injecting air into the vial first (equal to the dose you want to draw) makes drawing easier: the air raises vial pressure and does the work for you. Furthermore, when you push the plunger forward during injection, you overcome the back-pressure of the tissue so fluid flows out of the needle tip.
The Luer Lock seal
The Luer tip is a precise 6 percent taper, which means the surfaces of the needle hub and the syringe tip jam together under slight pressure and form a leak-proof seal. So this seal is independent of the external thread, which exists to physically lock the needle in place rather than to seal it. In particular, the lock thread stops the needle popping off during a thick-fluid injection, when back-pressure in the tissue would otherwise push against the needle hub. Furthermore, this is the main advantage of Luer Lock over Luer Slip for oil-based or small-volume high-pressure injections.
Why the graduations give accurate small doses
The barrel is marked in 0.01ml increments between 0 and 1ml. So a dose like 0.3ml of testosterone or 0.25ml of HRT is easy to read against the plunger seal's leading edge. In particular, reading the dose from the leading edge of the black rubber plunger (not the trailing edge or the rubber dome) is the standard technique that pharma packaging illustrates. Furthermore, keeping the syringe vertical at eye level during the dose read removes parallax error that can throw a reading off by 0.05ml or more.
Dead space and why it matters
Every syringe has a small volume of fluid that stays trapped in the needle hub and tip after you push the plunger all the way down. So this is the "dead space". In particular, in the Unifix 1ml Luer Lock design the dead space is small (typically 0.07ml with a short needle attached) but not zero, which is one reason compounded medicine volumes may need adjustment for the specific syringe-and-needle combination used. Furthermore, this is more important for very small doses, where dead space is a significant fraction of the dose.
The two-needle draw-and-inject method
Luer Lock design unlocks a two-needle workflow: draw up with a larger-bore needle (faster through viscous oil, less wear on the vial stopper), unscrew that needle, screw on a finer inject needle (less painful, less tissue trauma). So the needle swap only takes seconds. In particular, this is the main workflow advantage over fixed-needle syringes, where you are stuck with one compromise needle for both steps. Furthermore, this workflow is standard practice for TRT, HRT, and most compounded hormone injections.
Single use, by design
Each Unifix syringe is designed, sterilised, and labelled for single use only. So re-using a syringe risks contamination, needle-stick injury, and dulling of the needle tip (which makes the next injection more painful). In particular, the siliconised plunger loses lubricity after one draw-and-inject cycle, so a re-used syringe no longer gives smooth plunger action. Furthermore, UK sharps regulations treat used syringes as clinical waste that must go directly into a sharps bin.
How to use the Unifix 1ml Luer Lock syringe safely
Before you start
Wash your hands with soap and water.
Gather your medicine vial, one Unifix syringe, one draw needle, one inject needle, alcohol swabs, cotton wool, and your sharps bin.
Check the medicine label matches your prescription, and the expiry date is in date.
Check the syringe and needle blisters are intact. Discard any damaged blister packs.
Wipe the medicine vial rubber top with an alcohol swab and let it dry.
Drawing the medicine
Open the syringe blister at the plunger end. Do not touch the Luer Lock tip.
Screw the draw needle onto the syringe tip until it is firmly attached.
Remove the needle cap.
Pull the plunger back to draw in an equal volume of air.
Push the needle through the vial rubber top and inject the air into the vial.
Turn the vial upside down and slowly draw the correct dose (measured on the 0.01ml graduations).
Tap the barrel to bring any air bubbles to the top, then push them out gently.
Withdraw the needle from the vial.
Changing to the inject needle
Carefully unscrew the draw needle from the syringe.
Drop the used draw needle straight into the sharps bin. Do NOT re-cap.
Screw on a fresh inject needle.
Remove the new needle cap.
Push the plunger gently until a tiny drop of medicine appears at the needle tip (this clears any air).
Injecting
Choose your injection site according to your prescriber's advice (IM for oil-based hormones, SC for water-based medicines).
Clean the site with an alcohol swab if your prescriber advises, and let it dry.
For IM injection: insert the needle at 90 degrees, in a smooth, firm motion.
For SC injection: pinch a fold of skin and insert at 45 or 90 degrees, per prescriber advice.
Push the plunger down slowly and steadily.
Withdraw the needle straight out.
Press a piece of cotton wool onto the site if bleeding.
Rotating your injection sites
Rotate your injection sites to protect the tissue. So use a different spot each time, moving around a wider area rather than injecting the same patch repeatedly. In particular, this reduces the risk of lumps (lipohypertrophy), dents (lipoatrophy), and scarring. Furthermore, uneven absorption from damaged tissue can make dose control harder.
After the injection
Do not re-cap the needle.
Drop the whole used syringe with the inject needle attached straight into a 1-litre yellow sharps bin.
The draw needle should already be in the bin from earlier.
Write down your injection: dose, site, time. This helps you track rotation and spot problems.
Sharps disposal, in plain English
Why sharps disposal matters
A used needle can cause a needle-stick injury and pass on blood-borne infections. So every used needle (both draw and inject) must go into a proper sharps bin. In particular, this protects you, your family, cleaners, refuse collectors, and anyone else who may handle the waste.
What a sharps bin is
A sharps bin is a rigid, yellow plastic container with a lid that seals when full. So it is designed to withstand a needle-stick from the inside. Furthermore, sharps bins come in different sizes: 1-litre for home use is the standard household size.
How to get sharps disposal
Sharps disposal is arranged differently in different parts of the UK:
In many parts of England, your local council collects full sharps bins for free. So contact your council to arrange collection.
Some GP surgeries and pharmacies accept full sharps bins.
In some areas, a private clinical waste company handles collection.
Never put a sharps bin (full or empty) in your general household waste or recycling.
Buying a sharps bin
We stock 1-litre yellow sharps bins alongside the Unifix syringes and needles. So you can order everything you need in one go and start injecting safely from day one. In particular, ask our team if you'd like sharps disposal advice for your local area.
Choosing the right needles for your Unifix syringe
The Unifix syringe does not come with a needle. So you need to buy needles separately. In particular, most self-injectors use two needles per injection: one for drawing, one for injecting.
The draw-and-inject method
For most oil-based hormone injections:
Draw needle: 18G to 21G, 25mm to 40mm. Thicker gauge to pull the viscous oil into the barrel faster.
Inject needle: 25G to 27G, 25mm (IM) or 12mm to 16mm (SC). Finer gauge for a more comfortable injection.
Change the needle: unscrew the draw needle after drawing the dose, and screw on the fresh inject needle before injecting.
So you go through two needles per injection. Furthermore, both needles must go into the sharps bin after use.
Choosing gauge (needle diameter)
Needle gauge is the diameter. Higher numbers mean thinner needles:
18G to 21G: thick, for drawing viscous oils.
23G to 25G: mid-thickness, sometimes used for IM injection of oil.
25G to 27G: standard for injecting oil-based hormones once drawn.
27G to 30G: fine, more comfortable for daily insulin or water-based subcutaneous medicines.
Choosing length
Needle length choices depend on the injection route:
Subcutaneous (SC), 4mm to 16mm: for medicines that sit just under the skin (insulin, some hormones, B12).
Intramuscular (IM), 25mm to 38mm: for medicines that need to go into muscle (most oil-based testosterone, some antibiotics).
Always follow your prescriber's advice on injection route and needle length.
Warnings and precautions
Single-use only
Never reuse a syringe or needle. So use one syringe and one pair of needles for each injection, then discard in a sharps bin. In particular, reusing a needle blunts it, hurts more, and risks infection.
Never share syringes or needles
Sharing needles or syringes can pass on blood-borne infections including HIV, hepatitis B, and hepatitis C. So a syringe is for one person only, one use only.
Attach the needle properly
The Luer Lock needle must be screwed on until it is firmly attached before you draw or inject. So a loose needle can pop off or leak medicine. In particular, if you feel any resistance drop suddenly during injection, stop, withdraw, and check the needle.
Sterility
If the blister pack is torn, opened, or damaged, discard the syringe or needle. So do not use anything you are unsure of. In particular, contamination can cause a serious infection at the injection site.
Bleeding disorders and anticoagulation
People with bleeding disorders (haemophilia, von Willebrand) or on blood thinners (warfarin, apixaban, rivaroxaban, dabigatran, clopidogrel, dual antiplatelets) may bleed more from injection sites. So ask your prescriber before starting home injections, and press firmly on the site for longer after each dose.
Injection site infection
Signs of injection site infection include increasing redness, swelling, warmth, pain, or pus. So contact your GP if these develop, especially with a fever or feeling unwell.
Lipohypertrophy and lipoatrophy
Injecting repeatedly at the same spot can cause lumps (lipohypertrophy) or dents (lipoatrophy). So rotate your injection sites within and between recommended areas. Furthermore, medicine absorbs unpredictably from a lump or a dent, which can make dose control harder.
Needle-stick injury
If you accidentally stick yourself with a used needle, wash the area with soap and water, encourage the site to bleed, and contact NHS 111 or occupational health for advice. So urgent review matters if the needle carried a medicine that could cause harm at the wrong dose.
Storage and shelf life
Store at room temperature in the original box. So keep away from heat, direct sunlight, and damp. Furthermore, do not use after the expiry date printed on the box, as sterility is not guaranteed beyond that point.
Common injection reactions
Any injection can cause a local reaction at the injection site. So most reactions are mild and settle within a day:
Common (usually mild)
Brief stinging as the needle goes in.
A tiny drop of blood at the site.
Small red mark that fades within a day.
Mild bruising, particularly if the needle hits a small blood vessel.
Less common
Larger bruise (rotate to a new site next time).
Mild itching or a small raised area at the site.
A small lump that lasts a day or two.
Uncommon but important
Signs of infection (increasing redness, swelling, warmth, pain, pus, fever).
Persistent lump or dent at repeated injection sites (lipohypertrophy or lipoatrophy).
Severe pain or an unexpected change in how the medicine is working.
Oil spill from a loose needle during injection.
When to seek urgent help
Contact your GP if you develop signs of an injection site infection, an allergic reaction to your medicine, or an unexpected change in how your medicine is working. So for life-threatening symptoms, call 999.
Yellow Card scheme: report any suspected medical device problems via https://yellowcard.mhra.gov.uk or the Yellow Card app. Reporting helps make devices safer for everyone.
Drug and medicine compatibility with the Unifix syringe
A syringe is a device, not a medicine, so it does not have drug interactions in the usual sense. However, the right syringe for the job depends on what you are injecting, and some medicine-and-syringe pairings matter more than others. So if you are unsure whether the Unifix 1ml Luer Lock is the right fit for your specific medicine, check with your pharmacist before you order. In particular, our team can confirm compatibility against the medicine's SmPC or the device requirements set out by your prescriber.
What determines whether this syringe suits your medicine
The route of injection (subcutaneous, intramuscular, intradermal) and the volume per dose.
Whether the medicine comes in a vial (needs a draw-up step) or a prefilled device (does not).
The viscosity of the medicine, since thicker oil-based preparations draw up and inject more slowly through fine needles.
Any specific device guidance from your prescriber or from the medicine's SmPC (for example, insulin pump cartridges or siliconised syringe requirements).
Whether a Luer Lock needle lock is actually needed, which depends on injection pressure and the risk of needle detachment.
Medicines commonly drawn up with this syringe
The Unifix 1ml Luer Lock is widely used for small-volume parenteral medicines where a detachable needle is helpful. So typical pairings include:
TRT compounded preparations (testosterone enanthate, cypionate, propionate in oil).
GLP-1 analogue compounded preparations where vial-based supply is used (not prefilled pens).
Low-dose naltrexone (LDN) compounded liquid, where a 1ml syringe is used to measure the dose.
Vitamin B12 (hydroxocobalamin or cyanocobalamin) for subcutaneous or intramuscular injection.
Compounded hormone preparations drawn from vials.
Peptide or research-use preparations where a Luer Lock connection reduces leakage.
So the detachable needle design lets you use a larger-bore needle to draw up (faster, less wear on the stopper) and a finer needle to inject (less painful, less tissue trauma). In particular, this two-needle workflow is one of the main reasons a Luer Lock syringe is picked over a fixed-needle syringe.
When this syringe is not the right choice
Some medicines come with their own device or require a specific syringe type. So the Unifix 1ml Luer Lock is not the right choice for:
Insulin that is already supplied in a prefilled pen (use the pen, not a vial-and-syringe workflow).
Semaglutide, liraglutide, tirzepatide, dulaglutide where the licensed product is a prefilled pen (the prefilled pen is the licensed delivery device).
IV administration (needs a different syringe type and clinical setting).
Doses above 1ml (a 2ml, 3ml, 5ml, or 10ml syringe fits better).
Insulin from a vial, when a dedicated insulin syringe (U-100 graduation) is the standard and safer choice.
Medicines where the SmPC specifies a silicone-free, latex-free, or polycarbonate-free syringe (compatibility matters for certain biologics and compounded preparations).
Materials, latex, and silicone
The Unifix 1ml Luer Lock is a standard polypropylene barrel with a siliconised plunger seal. So this is the standard material set for most parenteral medicines. However, a few medicines (notably certain monoclonal antibodies and some compounded sterile preparations) have specific stability concerns with siliconised syringes if drawn up and stored for prolonged periods. In particular, draw up and inject promptly rather than storing the drawn-up syringe. Furthermore, the Unifix is latex-free, so it is suitable for patients with latex allergy.
Check with your pharmacist if unsure
If you are not sure whether the Unifix 1ml Luer Lock syringe is right for the medicine you are injecting, speak to your pharmacist before you order. So this is particularly important for compounded medicines, specials, or medicines prescribed off-label where device guidance may differ from the licensed product. In particular, our team at Courier Pharmacy can check the SmPC and your prescriber's instructions to confirm the right syringe and needle combination for your situation. Furthermore, we would always rather you take 2 minutes to check than find out mid-dose that the fit is wrong.
Frequently asked questions about Unifix 1ml Luer Lock syringes
What's the difference between a Unifix syringe and a Unisharp syringe?
Unifix syringes have a detachable Luer Lock needle connection. So you buy needles separately and can swap between draw and inject needles. In contrast, Unisharp syringes have a fixed needle permanently attached. Furthermore, Unifix is better for oil-based hormone injections, while Unisharp is simpler for insulin or single-needle water-based injections.
What does Luer Lock mean?
Luer Lock means the needle screws onto the syringe with a threaded collar. So the needle cannot pop off under pressure. In particular, this matters when injecting a thick oil, where pressure inside the barrel would push a friction-fit needle off.
What's the difference between Luer Lock and Luer Slip?
Luer Lock uses a screw-thread to hold the needle in place. In contrast, Luer Slip uses a friction fit; the needle just pushes on. So Luer Lock is safer for oil-based injections and higher-pressure medicines.
Do I need to buy needles separately?
Yes. Unifix syringes do not come with a needle. So you order needles separately, typically one draw needle (thicker, longer) and one inject needle (finer) per injection.
What size needle should I use to draw testosterone?
For most oil-based testosterone (Sustanon, Nebido, testosterone enanthate or cypionate), a 21G or 23G needle around 25mm to 40mm works well for drawing. However, always check with your TRT prescriber for your specific formulation.
What size needle should I use to inject testosterone?
For IM injection into the gluteal or thigh muscle, a 23G or 25G needle around 25mm to 38mm is standard. For subcutaneous testosterone, a 25G or 27G needle around 12mm to 16mm is common. In particular, your prescriber will confirm which route you should use.
Is Unifix suitable for IM injection?
Yes, once you attach a proper IM needle (typically 25mm or 38mm). So the syringe itself does not limit the route; the needle you screw on determines the route.
Is Unifix suitable for SC injection?
Yes, once you attach a proper SC needle (typically 12mm or 16mm). So again, the needle determines the route.
How accurate are the 0.01ml graduations?
Each small mark represents 0.01ml. So the syringe supports accurate dose measurement for most home hormone injections. In particular, for very small doses (under 0.05ml), a 0.5ml insulin syringe may be more precise.
How many syringes are in a pack?
Common pack sizes are 100 syringes, or larger boxes. So the standard household pack is a box of 100.
Are Unifix syringes CE-marked?
Yes. They are CE-marked medical devices, sold in the UK under the UK medical device rules.
Can I reuse a Unifix syringe?
No. Never reuse a syringe or needle. So one syringe and needle set is for one injection only, then straight into a sharps bin.
Can I share syringes with anyone else?
No. Sharing needles or syringes can pass on blood-borne infections including HIV, hepatitis B, and hepatitis C. So a syringe is for one person only.
How do I dispose of used syringes and needles?
Use a 1-litre yellow sharps bin. So drop the used needle and syringe straight in after each injection. When the bin is three-quarters full, seal it and arrange collection. In many parts of England, your local council collects full sharps bins for free.
Where can I get a sharps bin?
You can buy a 1-litre sharps bin from our website alongside your syringes and needles. Furthermore, GP surgeries and pharmacies may provide sharps bins on prescription for some patients.
Can I use this syringe if the blister is damaged?
No. If the blister is torn, opened, or damaged, discard the syringe. So sterility is not guaranteed once the pack is compromised.
Can I use this syringe past the expiry date?
No. Do not use after the expiry date printed on the box. So sterility is not guaranteed beyond that date.
What if the needle feels loose after I screw it on?
Do not use it. So a properly attached Luer Lock needle should feel firm with no wobble. In particular, use a fresh needle if you're unsure.
What if I get a needle-stick injury?
Wash the area with soap and water, encourage the site to bleed, and contact NHS 111 or occupational health for advice. So urgent review matters if the needle carried a medicine that could cause harm at the wrong dose.
Disclaimer
Disclaimer: This information is for education only and isn't a substitute for personal medical advice. Always follow your prescriber's instructions.
National Institute for Health and Care Excellence (2012, updated 2017). Healthcare-associated infections: prevention and control in primary and community care. NICE clinical guideline CG139. Available at: https://www.nice.org.uk/guidance/cg139
International Organization for Standardization (2017). ISO 7886-1:2017 Sterile hypodermic syringes for single use, Part 1: Syringes for manual use. Available at: https://www.iso.org/standard/70907.html
International Organization for Standardization (2021). ISO 80369-7:2021 Small-bore connectors for liquids and gases in healthcare applications, Part 7: Connectors for intravascular or hypodermic applications. Available at: https://www.iso.org/standard/79173.html
