Everything you need to know about lash extensions!
When it comes to lash extensions the variety is almost endless! It can be tricky knowing the ins and outs. But here’s a breakdown of the major differences you’ll find when it comes to lash extensions.
Length
Just like our natural lashes, lash extensions come in all different lengths, ranging from as small as 6mm long all the way up to a whopping 20mm. I know what you’re thinking ‘err maahh gaawd where do I find 20mm lash extensions’. NO! This is waaay too long for anyone. The rule when lashing is actually to extend the lash no more than 1/3 of the natural lash. Whilst most lash artists will bend this rule a little, anything above 13mm is generally very unnatural.

Thickness
The thinnest lash extensions begin at 0.05mm tiny right! Especially considering human hair is roughly 0.06-0.08mm. These ultra thin lashes are made for the purpose of creating mega volume lashes ie. Multiple lash extensions per natural lash. Classic lash extensions can be made up to a very unnatural 0.25mm this is more than 4 times the thickness of a natural lash.
Style
As with most things, fashion comes and goes, just like lash styles. Here’s some of the most popular and an upcoming style to look out for!

Cat eye – starting with shorter lengths on the inner corners gradually building to the longest lengths on the outer corner

Doll/drama – Using the same, or mostly the same length for all the lashes

Squirrel – Using shorter lashes on the inner and out corners building to the longest length in the centre

Hollywood/flirty – Using a combination of short and long lashes throughout the eye to create a more 3D effect.
Curl
When Eyelash Extensions first arrived on the scene typically J & B curl were used most as they mimicked the natural lash curl. Now, we find most people wanting a more dramatic open eye look, so most favour C & D curl





Volume
- Classic – Classic lashes are when a lash technician applies one lash per every natural lash, we recommend no thicker than 0.15mm for this technique.
- 2D-7D volume – Volume lashes are probably the most popular choice when in comes to extensions, the number corresponds to how many lash extensions are applied to each natural lash. The more volume, the thinner the lashes should get. Eg. 2D you could use 2×1.0mm lashes, for 3-4D 0.07mm, 5-7D 0.05mm.
- Hybrid – Hybrid mixes both volume and classic lash extensions to give the illusion of thicker and darker lashes.
Material
- Polyester blend – By far the most natural feeling lashes, a polyester blend is soft and flexible
- Acrylic – Acrylic lashes are pretty easy to spot, they are very shiny and feel stiff and rigid, definitely not a natural look or feel
- Mink – As horrible as it is, you can get real mink lash extensions. This is something we are very much against and would advise people to avoid supporting this animal cruelty trade.
Colour/Special FX
Yes! A trend that hasn’t seemed to take off yet is coloured lashes. Often people will refer to them as ‘mermaid’ lashes. You can also get special FX lashes that include feathers, glitter and patterns.
Other fun facts:
- You can actually get straight brow extensions as well! Using a special clear glue the lashes are glued to the skin rather than the hair, these types of extensions typically only last a day or two.
Want to learn how to lash just like us? Visit our page and read all about our Eyelash Extension Training Course
Not too keen on learning but want you lashes done by the best? Not too keen on learning but want your lashes done by the best? Book your eyelash extensions with us!
FAQS:
Many clients may benefit from knowing that lash extensions require ongoing maintenance, consistent aftercare, and careful choice of lash technician before committing to their first set. Lash extensions are individual synthetic, silk, or mink-style fibres applied one at a time to natural lashes using a semi-permanent adhesive, and the quality of application can directly affect comfort, longevity, and natural lash health.
Things many first-time clients wish they had known can include:
- The full application typically takes 90–180 minutes depending on the style chosen
- Lashes may need topping up every 2–4 weeks as natural lashes shed
- Daily care matters — using oil-based products, sleeping face-down, or rubbing the eyes may shorten lash life
- Natural lash health may limit what is safe to apply — heavy lashes on fine natural lashes can cause damage
- Some adhesives contain ingredients that may trigger allergic reactions, which is why a patch test is generally recommended for first-time clients
- The technician’s training and hygiene practices can affect the result
Practical considerations before booking may include:
- Limit caffeine immediately before — it can cause eye flutter that may complicate application
- Arrive with clean, makeup-free eyes
- Plan around 2 hours of stillness — the eyes stay closed for the entire appointment
- Schedule the first set well before any event to allow time for adjustment
Pre-treatment guidance is detailed in the eyelash treatments before care guide, and aftercare is in the eyelash treatments after care document. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service may help determine individual suitability. Individual risks and suitability should be discussed at a consultation.
Lash extensions may offer cosmetic benefits but also have practical drawbacks that may be worth considering before committing to ongoing wear. The downsides typically relate to maintenance time, ongoing cost, potential effects on natural lashes, and lifestyle adjustments required to maintain the result.
Potential downsides of lash extensions can include:
- Ongoing maintenance — top-up appointments every 2–4 weeks may be required to maintain a consistent look
- Cumulative cost — the cumulative cost of regular infills can add up over a year
- Aftercare restrictions — oil-based products, certain cleansers, and mechanical eye-rubbing may need to be avoided
- Potential natural lash impact — extensions that are too heavy or poorly applied may stress natural lashes, leading to breakage or premature shedding
- Allergic reactions — some clients may develop sensitivity to the adhesive, with symptoms that can include itching, redness, swelling, or watery eyes
- Sleep adjustment — many wearers prefer to sleep on their back to extend lash life
- Limited eye-makeup options — waterproof mascara and oil-based eye products are generally not compatible
- Difficulty with eye procedures — lash extensions may interfere with eye exams, contact lens fitting, and certain eye treatments
When downsides may become significant:
- Recurrent allergic reactions
- Visible natural lash thinning over time
- Lifestyle conflicts (swimming, contact sports, frequent rubbing)
- Difficulty maintaining the appointment schedule
Pre-treatment guidance is in the eyelash treatments before care instructions, and aftercare in the eyelash treatments after care guide. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service allows discussion of individual suitability.
Lash extension care typically follows a clear set of dos and don’ts that may help protect both the extensions and the natural lashes underneath. Following the recommendations consistently in the first 24–48 hours after application — and across the lifespan of the lashes — can affect how long the set lasts and how the natural lashes recover.
Do:
- Keep lashes dry for the first 24 hours after application
- Clean lashes daily with a lash-safe foam cleanser to remove oil and debris
- Brush lashes gently with a clean spoolie each morning
- Sleep on your back or side with a silk pillowcase to reduce friction
- Use only oil-free, lash-safe makeup and removers
- Attend regular infill appointments every 2–4 weeks
- Inform the technician of any sensitivity or allergic reactions promptly
Don’t:
- Don’t wet lashes or use steam, saunas, hot showers, or pools for the first 24 hours
- Don’t rub, pull, or pick at lashes
- Don’t use oil-based products near the eyes (cleansers, makeup removers, eye creams)
- Don’t sleep face-down or press the lashes against pillows
- Don’t use waterproof mascara, eyeliner, or curlers on extensions
- Don’t try to remove extensions at home — improper removal may damage natural lashes
- Don’t use cotton balls or cotton pads, which can snag the lashes
- Don’t apply heat directly to the lashes (curling tools, hot air dryers close to the face)
Following these recommendations is detailed in the eyelash treatments after care document. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service provides personalised aftercare for individual lash needs.
Avoiding certain products and habits in the 24 hours before a lash extension appointment may help the adhesive bond properly and reduce the risk of irritation or premature lash loss. Clean, oil-free, mascara-free lashes are typically preferred for application.
What to generally avoid before a lash extension appointment can include:
- No mascara on the day of application — even traces may prevent the adhesive from bonding
- No oil-based eye creams, makeup removers, or moisturisers for at least 24 hours before
- No waterproof eye products — these can be particularly difficult to remove completely
- No lash curlers in the 24 hours before — curled lashes may not sit evenly during application
- No tinting or perming the natural lashes within 48 hours before extensions
- Limit caffeine immediately before — caffeine can cause eye flutter that may complicate application
- Limit alcohol the night before — may contribute to eye twitching or dryness
- No contact lenses during the appointment — many technicians prefer them removed
- Avoid lying face-down or rubbing the eyes on the day of application
Practical preparation steps may include:
- Cleanse the eye area thoroughly the night before with an oil-free cleanser
- Plan a low-screen-time day before to reduce eye fatigue
- Wear comfortable clothing for a 90–180 minute appointment
- Arrive 5–10 minutes early to relax before the treatment begins
- Disclose any medication, allergies, or recent eye procedures at check-in.
The eyelash treatments before care guide details all pre-treatment recommendations. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service confirms preparation steps for individual circumstances.
A poorly executed lash extension set may show clear visual and tactile signs immediately after the appointment and in the days that follow. Recognising these signs may help clients raise concerns with the technician or seek a corrective appointment before natural lashes are affected.
Visual signs of a poor lash extension job can include:
- Stickies — extensions glued to multiple natural lashes, which may prevent the natural shedding cycle and pull on the lash line
- Uneven lengths — extensions placed without consideration for the natural lash growth pattern
- Visible glue dots — clumps of adhesive on lash bases, often whitish or crusty
- Lashes touching the skin — extensions glued to or resting on the eyelid skin
- Asymmetry — one eye noticeably different in volume or curl from the other
- Extensions on baby lashes — applied to immature natural lashes that may not support the weight
- Twisted or crossed extensions — sitting at conflicting angles
- Crowding — extensions packed densely without proper isolation, which may fuse natural lashes together
Sensory signs of poor application can include:
- Burning, stinging, or itching during or after the appointment
- Persistent watering eyes for more than a few hours
- Tightness or pulling sensation
- Eye irritation that worsens over 24 hours
Longer-term signs of poor work can include:
- Natural lashes thinning, breaking, or shedding earlier than expected
- Set falling out within 1 week of application
- Visible bald patches on the lash line
If concerns arise, contact the original technician promptly and avoid attempting to remove extensions at home. The eyelash treatments after care guide includes guidance on identifying issues. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service may help assess and correct application concerns.
Lash extensions may not be suitable for every client at every time, and individual circumstances may make it safer to delay or avoid treatment. Identifying these factors before booking may help protect eye health and natural lash integrity.
Situations where lash extensions may not be appropriate can include:
- Active eye conditions — conjunctivitis, blepharitis, styes, or ongoing eye infections may need to resolve before treatment
- Known adhesive allergies — clients with prior reactions to cyanoacrylate-based adhesives may experience worsening reactions
- Recent eye surgery or procedures — including laser eye surgery (LASIK), cataract surgery, or eyelid procedures within recommended healing periods
- Pregnancy and breastfeeding — sensitivity and hormonal changes may affect adhesive tolerance; many clinics recommend a patch test or postponement
- Chemotherapy or radiation treatment — natural lashes may be fragile or shedding, which may make extensions inappropriate
- Trichotillomania — clients who pull at lashes may damage natural lashes when extensions are attached
- Very fine or weak natural lashes — heavy extensions may stress the natural lash and cause breakage
- Severe dry eye syndrome — extensions may worsen symptoms
- Special-event timing only — clients seeking lashes for one event may find the maintenance impractical
When postponement may be advised:
- Within 24–48 hours of strenuous exercise, swimming, or sauna use
- Immediately before or after a long-haul flight (puffy eyes may affect application)
- During severe hayfever or allergy flare-ups
A patch test 24–48 hours before the first application is generally recommended for clients with sensitive skin or any uncertainty about adhesive tolerance. The eyelash treatments before care guide details pre-treatment recommendations. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service may help confirm individual suitability.
A first-time lash extension appointment typically takes 90 to 180 minutes and involves lying on a treatment bed with eyes closed for the duration of the application. The technician applies individual extensions one at a time to the natural lashes using a fine-tipped adhesive, working through both eyes in alternating sections.
Step-by-step first-time appointment experience can include:
- Consultation — discussion of desired length, curl, thickness, and style (classic, hybrid, or volume)
- Patch test review — confirmation of any sensitivity from a prior patch test
- Eye protection — under-eye pads applied to protect lower lashes and skin
- Lash isolation and cleansing — natural lashes cleaned with an oil-free foam to prepare for adhesive
- Mapping — the technician plans extension placement based on eye shape and natural lash growth
- Application — 90–150 minutes of one-by-one extension placement, with eyes closed throughout
- Drying and brushing — extensions are gently brushed and allowed to fully cure
- Aftercare briefing — recommendations for the first 24 hours and ongoing maintenance
What to expect during the appointment may include:
- A comfortable lying position with eyes closed (many clients relax or nap)
- Gentle pressure and a faint cool sensation from the adhesive
- Quiet music or silence to allow concentration
- Occasional position adjustments
What to expect immediately after may include:
- Slight sensitivity for a few hours as the adhesive fully cures
- Eyes feeling slightly different — heavier or more “open”
- Recommendations to avoid water and steam for 24 hours
The eyelash treatments before care and after care guides provide preparation and aftercare details. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service may help plan the right first set.
Lash extensions generally should not hurt during or after a correctly performed application. The procedure involves applying individual extensions to natural lashes without touching the skin or pulling on the lash root, so many clients describe the experience as relatively relaxing rather than painful.
What may be expected as normal during a first-time appointment can include:
- A gentle cool sensation from the adhesive
- Slight pressure from the under-eye pads
- A faint tickling feeling as the technician works
- Mild sensitivity to the eye area if eyes are kept closed for an extended period
What may not be normal and could indicate a problem can include:
- Sharp pain or burning during application
- Stinging or watering eyes throughout the appointment
- A pulling sensation on the lash line
- Persistent discomfort more than a few hours after the appointment
- Swollen, red, or itchy eyelids in the 24 hours following
Possible causes of pain or discomfort can include:
- Adhesive fumes irritating sensitive eyes (more common in poorly ventilated spaces)
- Eyes partially open during application allowing fumes to contact the eye surface
- Extensions touching the eyelid skin
- Allergic reaction to the adhesive
- Extensions applied to baby lashes or skin
If pain develops:
- Inform the technician promptly if discomfort occurs during the appointment
- Apply a cool compress and contact the clinic if pain develops afterwards
- Do not attempt to remove extensions at home
The eyelash treatments after care document outlines what to do if reactions occur. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service allows discussion of sensitivity and adhesive options before booking.
Eyelash extensions may carry several potential risks that should be understood before the first appointment, although for many clients these risks can be minor and manageable with proper technique and aftercare. The risk categories typically relate to allergic reactions, mechanical effects on natural lashes, and infection.
Potential risks of eyelash extensions can include:
- Allergic reactions to adhesive — cyanoacrylate-based glues may cause itching, redness, swelling, or watering eyes; symptoms can appear immediately or develop after several applications
- Eye irritation — adhesive fumes during application may irritate sensitive eyes, particularly with eyes partially open
- Bacterial infections — poor hygiene during application or inadequate cleaning afterwards may introduce bacteria to the eye area
- Damage to natural lashes — extensions that are too heavy, applied to baby lashes, or removed improperly may cause breakage and thinning
- Traction alopecia — repeated stress on the lash line over time may contribute to thinning
- Corneal injury — very rare, but possible if extensions are applied too close to the lash line or fall into the eye
- Contact dermatitis — sensitivity around the eyelid skin from prolonged adhesive exposure
- Stickies — extensions glued to multiple natural lashes, disrupting the natural shed cycle
- Increased eye dryness — denser lashes may slow tear film evaporation in some clients
Risk reduction strategies may include:
- Choosing a qualified, experienced technician using sealed, in-date adhesive
- Requesting a patch test before the first application
- Following aftercare instructions consistently
- Attending regular infills rather than allowing extensions to grow out unevenly
- Having extensions professionally removed rather than picking them off
The eyelash treatments before care and after care guides cover risk management. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service may help identify individual risk factors.
Lash extension risks typically fall into three main categories: allergic and irritant reactions, natural lash effects, and infection. Many risks may be reduced by choosing a qualified technician, requesting a patch test, and following aftercare instructions consistently.
Risk category 1 — Allergic and irritant reactions:
- Adhesive sensitivity may develop on a first application or after repeated exposures
- Symptoms can include itching, redness, swelling, watering eyes, and burning
- Some clients tolerate one adhesive but react to another, so disclosure of brand history may be helpful
- Severe reactions are rare but may require medical assessment
Risk category 2 — Natural lash effects:
- Extensions that are too heavy may stress the natural lash and cause breakage
- Application to immature “baby lashes” may pull them out prematurely
- Improper at-home removal often pulls out natural lashes along with extensions
- Long-term wear without breaks may contribute to cumulative thinning
Risk category 3 — Infection and inflammation:
- Poor hygiene during application may introduce bacteria to the lash line
- Inadequate cleaning of extensions may trap oil, makeup, and debris around the follicles
- Existing blepharitis or styes may worsen with extensions in place
Other risks can include:
- Corneal abrasions (very rare) if extensions detach into the eye
- Worsened dry eye symptoms
- Contact dermatitis on the eyelid skin
Practical risk reduction may include:
- Patch test before the first application
- Maintain daily lash hygiene with a lash-safe foam cleanser
- Avoid oil-based products near the eyes
- Schedule rest periods between full sets every 6–12 months if recommended by the technician
The eyelash extensions service at Injex Clinics is provided by qualified technicians. A consultation is recommended to discuss individual risk factors before booking. Individual risks and suitability should be discussed at a consultation.
Ophthalmologists may view lash extensions as cosmetically acceptable for many clients when applied by qualified technicians, but they often raise specific concerns about eye health that clients may want to consider. The medical literature notes potential issues including contact dermatitis, conjunctivitis, mechanical lash effects, and occasionally more serious complications.
Common ophthalmological observations about lash extensions can include:
- Bacterial colonisation — extensions may trap debris and oil around the lash line if not cleaned regularly, which can contribute to blepharitis
- Tear film disruption — denser lashes may slow tear film evaporation, which can sometimes worsen symptoms in clients with existing dry eye syndrome
- Adhesive reactions — cyanoacrylate-based adhesives are recognised causes of allergic contact dermatitis in the eyelid skin
- Mechanical lash loss — repeated cycles of extension wear and removal may contribute to traction alopecia at the lash line over years
- Risk of corneal abrasion — uncommon but possible if extensions detach into the eye
Ophthalmologist recommendations clients may hear:
- Maintain daily lash hygiene
- Take breaks from extensions periodically to allow natural lashes to recover
- Avoid extensions during active eye conditions or after recent eye surgery
- Choose a qualified, hygienic technician
- Seek medical assessment if persistent redness, pain, swelling, or vision changes occur
When ophthalmological assessment may be advised:
- Persistent eye irritation that does not resolve after extension removal
- Vision changes
- Severe allergic reaction symptoms
- Recurrent eyelid infections
- Significant natural lash thinning
The eyelash treatments after care guide covers eye hygiene during extension wear. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service may help identify pre-existing factors that may affect suitability. Clients with chronic eye conditions may want to consult their ophthalmologist before booking.
Eyelash extensions may not be suitable for every client, and certain medical, ophthalmological, and lifestyle factors may make treatment unsafe or impractical. Pre-treatment screening at consultation may help identify these factors before application.
Clients who may not be suitable candidates can include:
- Active eye conditions — conjunctivitis, blepharitis, styes, or ongoing eye infections
- Known adhesive allergies — particularly cyanoacrylate-based glue sensitivity
- Recent eye surgery — LASIK, cataract surgery, or eyelid procedures within recommended healing periods (typically several weeks to months)
- Chemotherapy or radiation patients with fragile or shedding lashes — medical clearance may be required
- Trichotillomania — clients who pull at lashes may damage natural lashes when extensions are attached
- Severe dry eye syndrome — extensions may worsen symptoms
- Severe alopecia areata affecting the lash line — natural lashes may not support extensions
- Pregnancy and breastfeeding — sensitivity and hormonal changes may affect adhesive tolerance; some clinics recommend postponement, others perform a patch test first
- Clients with very fine or weak natural lashes — heavy extensions may cause breakage
- Recent chemical lash treatments — perms or tints within 48 hours may interfere with adhesive bonding
Lifestyle factors that may make extensions impractical can include:
- Frequent swimming, sauna, or hot yoga without willingness to adjust aftercare
- Inability to attend regular 2–4 week infill appointments
- Habitual eye rubbing or sleeping face-down
Children and minors:
- Lash extensions are generally not recommended for under-18s due to natural lash maturity and adhesive sensitivity considerations
A patch test 24–48 hours before the first application is generally recommended for clients with sensitive skin or any uncertainty about adhesive tolerance. The eyelash treatments before care guide details pre-treatment recommendations. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service may help determine individual suitability.
False eyelashes — including strip lashes, cluster lashes, and semi-permanent extensions — may not be appropriate for every client, and certain conditions or sensitivities may make application unsafe or unsuitable. The factors overlap with semi-permanent extension contraindications.
Clients who may want to avoid false eyelashes can include:
- People with adhesive allergies — cyanoacrylate or latex-based glues used in strip and extension adhesives may trigger reactions
- Active eye infections or inflammation — conjunctivitis, styes, blepharitis, or chalazia may need to resolve first
- Recent eye surgery patients — including LASIK, cataract, or eyelid procedures within their healing window
- Severe dry eye syndrome — false lashes may interfere with the tear film and worsen symptoms
- Trichotillomania — repeated pulling may damage natural lashes whether false lashes are attached or not
- Skin conditions on the eyelid — eczema or psoriasis flares around the lash line
- Children and young teenagers — natural lashes are immature and skin may be more reactive
- Chemotherapy patients with very fragile lashes — medical guidance is recommended
- Clients sensitive to the eye area — those who struggle to tolerate any eye area products
Specific issues with strip and cluster lashes (as distinct from extensions) can include:
- Strip lashes glued daily may cause repeated irritation
- Cluster lashes applied in groups can stress the natural lash to which they are attached
- DIY application without training may increase the risk of glue contact with the eye
When professional alternatives may suit better:
- A lash lift or tint may achieve a similar look without extensions
- A patch test with a sensitive adhesive may help identify suitability for semi-permanent options
- A consultation may reveal underlying eye conditions worth addressing first
The eyelash extensions service at Injex Clinics includes consultation to help identify suitability factors. A consultation with a qualified lash technician is recommended before booking.
Eye pain after a lash extension appointment is not typical and usually points to one of several specific causes that may benefit from prompt assessment. Mild sensitivity for a few hours can be common, but persistent pain, burning, or discomfort beyond 24 hours may indicate a problem worth attention.
Possible causes of post-extension eye pain can include:
- Adhesive fumes contacting the eye surface — if eyes were partially open during application, cyanoacrylate vapours may have irritated the conjunctiva or cornea
- Allergic reaction to the adhesive — symptoms may include itching, redness, swelling, and burning, sometimes hours or days after application
- Extensions touching the eyelid skin — improperly placed extensions may pull on or irritate the lid margin
- Stickies — multiple extensions bonded to one natural lash may create a pulling sensation
- Corneal abrasion — very rare, but possible if an extension scratched the eye during or after application
- Bacterial irritation — poor hygiene during application may introduce bacteria
- Pre-existing dry eye — extensions may worsen symptoms in clients with this condition
Immediate steps if eye pain develops can include:
- Apply a cool, clean compress to the eyelid
- Use lubricating eye drops (preservative-free) if comfortable
- Do not rub or pick at the lashes
- Contact the technician for advice and possible removal
- Seek medical assessment if pain is severe, vision is affected, or symptoms worsen
When to seek urgent medical attention may include:
- Sharp pain or sensitivity to light
- Vision changes or blurring
- Significant eyelid swelling
- Persistent redness lasting more than 48 hours
- Discharge from the eye
The eyelash treatments after care document covers typical versus concerning reactions. A consultation with a qualified lash technician at the Injex Clinics eyelash extensions service may help identify sensitivity factors before future appointments. Clients with ongoing eye discomfort may want to consult their GP or optometrist.