injectbeauty

Last updated September 2026

Everything they injectgoes to a different depth.

That one fact explains most of what confuses people. Toxin reaches the muscle. Filler is placed in the dermis, the fat or on the bone. They are not versions of each other, and they do not fix the same things.

Cross-section of facial skin showing where each injectable is placedLayers from the surface down: epidermis, dermis, fat, muscle, bone. Five needles enter to different depths. A biostimulator stops in the deep dermis. PDO threads sit in the fat. Deoxycholic acid goes into the fat. Botulinum toxin reaches the muscle. Hyaluronic acid filler is placed in the dermis, the fat or on the bone.BiostimulatorPDO threadsDeoxycholic acidBotulinum toxinHA fillerEpidermisDermisFatMuscleBone Cross-section of facial skin showing where each injectable is placedLayers from the surface down: epidermis, dermis, fat, muscle, bone. Five needles reach different depths, each labelled: biostimulator in the deep dermis, PDO threads and deoxycholic acid in the fat, botulinum toxin in the muscle, and hyaluronic acid filler in the dermis, the fat and on the bone.BiostimulatorPDO threadsDeoxycholic acidBotulinum toxinHA fillerEPIDERMISDERMISFATMUSCLEBONE
Depths are shown in proportion to each other, not to scale. Where a practitioner places a product depends on the area, on your anatomy and on the product itself.

A line from squeezing and a line from emptiness are different problems.

The same concern can have different causes. Lines that appear when you move are driven by muscle. Hollows come from lost volume. Sagging comes from loose skin and changes in the tissue beneath it. Each treatment acts mainly on one of these, so a treatment aimed at the wrong cause tends to disappoint. Toxin, for example, does little for hollows or loose skin, although it can soften some lines at rest over time. Most faces show a mix of causes. Working out which apply to you needs an in-person assessment by a qualified clinician. A mirror or a photo cannot do it. This page can help you follow that conversation. It cannot replace it.

What each one actually is.

DERMIS, DEEP

Biostimulators

REVERSIBLE NO

Sculptra, which is poly-L-lactic acid, and Radiesse, which is calcium hydroxylapatite

Biostimulators prompt your body to build its own collagen. The two main types behave differently. Sculptra, made of poly-L-lactic acid, works mainly through collagen. It looks fuller for a few days because of the water it is mixed with. That early fullness fades, and the real result builds gradually over months, usually across several sessions. Radiesse, made of calcium hydroxylapatite, does both. Its gel carrier adds some volume straight away, then it stimulates collagen over the following months. Both are placed beneath the skin, in the deep layers or on bone. Neither can be reliably dissolved. Lumps, nodules and granulomas are the main complications and can appear months later. Placement too near the surface makes visible nodules more likely. Neither is used in the lips or close around the eyes. After Sculptra you are usually told to massage the area several times a day for several days.

  • Where it goesBeneath the skin: deep dermis, fat layer or on bone. Not lips or around the eyes.
  • When you see itSculptra: early swelling fades, then gradual change over 2-3 months, several sessions. Radiesse: some volume at once, collagen over months.
  • How longSculptra: up to about 2 years. Radiesse: about 12-18 months.
  • ReversibleNo. Neither can be reliably dissolved. Nodules may need further treatment or surgery.
  • Usual areasBroad flat regions: cheeks, temples, jawline, and off the face on chest, arms and buttocks
WILL NOT

It is not a shaping tool.

Sculptra will not give an instant result. Neither can be dissolved if you dislike it. Neither is for lips or around the eyes.

FAT, UPPER

PDO threads

REVERSIBLE NOT CLEANLY

Polydioxanone, the same material used in absorbable surgical stitches

A thread lift uses dissolving sutures, usually made of PDO, PLLA or PCL. They are passed through a needle or cannula into the fat layer beneath the skin. Barbs or cones on the thread grip the tissue and hold it in a lifted position. As the thread dissolves, it prompts some collagen to form around it. The lift is modest and settles back over months. Complications include dimpling or puckering, threads you can see or feel, a thread working its way out through the skin, infection, and pain when you move your face. Rarely, a facial nerve or the parotid salivary gland is injured. Threads can sometimes be removed, but not always easily or completely.

  • Where it goesIn the fat layer beneath the skin (subcutaneous), not in the skin itself.
  • When you see itRepositioning is immediate, then it settles over 2-4 weeks
  • How longVisible lift usually 6-12 months, often less. Threads dissolve over months, depending on material.
  • ReversibleNot cleanly. A thread can sometimes be removed early if something is wrong
  • Usual areasJawline, cheeks, brow, neck
WILL NOT

It is not a facelift.

Will not match a surgical facelift. Will not lift heavy or very loose skin. Will not last.

FAT

Deoxycholic acid

REVERSIBLE NO

Sold as Kybella

Deoxycholic acid is a synthetic version of a substance your body uses to break down dietary fat. It is sold as Kybella or Belkyra. Injected into fat under the chin, it breaks open the walls of fat cells, and your body clears them over the following weeks. Destroyed cells do not come back, but the fat cells that remain can still grow if you gain weight. It damages any tissue it reaches, not only fat, so placement matters. Swelling, bruising, numbness and firmness are expected and can last weeks. Injury to the marginal mandibular nerve, which runs along the jaw, can leave your smile uneven for weeks to months. Trouble swallowing, skin ulceration and hair loss in the beard area have also been reported. It will not tighten loose skin. It is not a weight-loss treatment.

  • Where it goesInto the fat itself, most often the pocket under the chin
  • When you see itSwelling for 1-2 weeks. Change visible after 4-6 weeks. Usually 2-4 sessions, up to 6, at least 1 month apart.
  • How longThose fat cells are gone for good, though the cells left behind can still enlarge with weight gain
  • ReversibleNo
  • Usual areasFat under the chin. Other areas are off-label. Approvals vary by country.
WILL NOT

It is not a weight loss treatment.

It does nothing for loose skin. If what bothers you under your chin is lax skin rather than fat, taking the fat away can leave it looking worse.

MUSCLE

Botulinum toxin

REVERSIBLE NO

Sold under brand names including Botox, Dysport, Xeomin, Jeuveau, Daxxify and Letybo. Approved brands differ by country

Botulinum toxin blocks the signal from nerve to muscle, so the treated muscle relaxes for a few months. It softens lines that form when you move. It does not add volume, fill hollows or lift loose skin. Lines that show when your face is still may soften over repeated treatments, but they rarely disappear. Brands are measured in different units, so a dose of one brand is not the same as a dose of another. Some people stop responding over time, sometimes because their body makes antibodies to the toxin.

  • Where it goesInto the muscle, or into the skin when it is used for sweating
  • When you see it2-5 days. Full effect by about 2 weeks.
  • How longUsually 3-4 months, sometimes longer. Unwanted effects last as long.
  • ReversibleNo. There is no antidote. Unwanted effects can last weeks to months.
  • Usual areasFrown lines, forehead, crow's feet. Approved areas differ by brand and country. Lip, jaw, neck and other areas are often off-label.
WILL NOT

It adds no volume whatsoever.

Hollow temples, flat cheeks and deep folds are structural problems, and toxin does nothing for them.

BONE · FAT · DERMIS

Hyaluronic acid filler

REVERSIBLE LARGELY

Sold as Juvederm, Restylane, RHA, Belotero, Teosyal and others

Hyaluronic acid filler is a gel based on a sugar molecule your body already makes. It is injected into or beneath the skin, or onto bone, to add volume or change shape. You see the result straight away, along with some swelling that settles. It will not relax muscles or tighten loose skin. The visible effect fades, but imaging shows the gel can stay in tissue for years. Over time it can move from where it was placed. Placed too near the surface, it can show as a bluish tint, known as the Tyndall effect. Under the eyes it can hold water and cause lasting puffiness. Repeated top-ups can build up because older gel may still be there. Lumps or swelling can also appear months later, sometimes after an infection, dental work or a vaccination.

  • Where it goesIn the dermis, in the fat, or deep near the bone, chosen for the goal
  • When you see itImmediately, but swelling means you are not judging the real result until 2 weeks
  • How longVisible effect about 6-24 months, shorter in lips. Gel can stay in tissue for years.
  • ReversibleLargely. Hyaluronidase breaks it down. May need repeat sessions. Can cause allergy. Cannot undo damage already done.
  • Usual areasCheeks, midface, temples, jawline, chin, lips, under the eye, nose. Approved areas vary by product and country. Higher vascular risk: nose, between the brows, forehead, temples, folds beside the nose.
WILL NOT

More of it does not read as younger.

It does not stop a muscle moving, so it will not settle a line made by squeezing. Past a certain point it simply reads as filled, which is a different look and one most people did not ask for.

Only one of these can be undone, and not always. That is why the next two sections exist.

Results fade. Some material stays. Some harm is permanent.

Ranges, not promises. How long a result holds depends on the product, where it was placed, how much the area moves and how fast your body clears it. Two people treated on the same day can be six months apart.

How long each treatment lastsRanges on a scale from now to two years. Botulinum toxin 3 to 4 months. PDO thread lift 6 to 12 months. Radiesse 12 to 18 months. Hyaluronic acid filler 6 to 24 months. Sculptra up to 2 years and beyond. Deoxycholic acid removes fat cells permanently, shown beyond a break in the scale.Botulinum toxin3-4 monthsPDO threads, the lift6-12 monthsRadiesse12-18 monthsHyaluronic acid filler6-24 monthsSculptraup to 2 yearsDeoxycholic acidPERMANENTnow6 months1 year18 months2 years

Most of what goes wrong is temporary. Some of it is not.

Bruising, swelling, tenderness and small lumps are common, expected and settle on their own. Infections are uncommon; most respond to treatment, though some around filler are persistent and need prolonged treatment. If you get cold sores, say so before any lip treatment.

Bruising, headache and tenderness at the injection points are common. Toxin placed slightly off, or spreading beyond where it was put, can drop an eyelid or a brow, or leave your smile uneven. After a lip flip, drinking through a straw or saying some words can be harder. After jaw muscle treatment, your smile can change or the muscle can bulge when you clench. Neck treatment can affect swallowing. These effects are temporary but may last weeks to months. Some can be partly eased, such as a drooping eyelid with prescription eye drops. None can be switched off. Rarely, toxin spreads well beyond the injection site. Trouble swallowing, speaking or breathing, or widespread muscle weakness, in the days or weeks after treatment is an emergency. Call emergency services. The risk is higher with neck treatment and larger doses. Unlicensed or counterfeit toxin carries a much higher risk and has caused botulism-like illness needing hospital treatment.

Vascular occlusion is the one that matters. If filler is injected into a blood vessel, or presses one closed, the tissue that vessel supplies loses its blood supply and the skin can die. If the material reaches vessels that supply the eye or the brain, it can cause permanent blindness or, very rarely, a stroke. The risk is highest around the nose, between the brows, the forehead, the temples and the folds beside the nose.

Hyaluronic acid filler differs from other fillers in one important way in an emergency. An enzyme called hyaluronidase can break it down, and a practitioner who has it on site can act at once. It is not a guarantee. It works best on blockages in the skin that are treated early, and it may need repeated doses. It cannot reliably restore sight once vision has been lost. It will not bring back tissue that has already died. Hyaluronic acid fillers account for a large share of reported cases of blindness. Biostimulators and permanent fillers have no equivalent enzyme. Hyaluronidase is also not the only emergency medicine a clinic needs. Severe allergic reactions are treated with adrenaline. None of this is a view on whether you should have any treatment.

CALL EMERGENCY SERVICES NOW · DO NOT WAIT FOR YOUR INJECTOR

  1. VISIONAny change in your vision, or pain in or behind the eye
  2. EYEA drooping eyelid or double vision
  3. STROKESudden face droop, weakness, trouble speaking or confusion
  4. BREATHINGTrouble swallowing, speaking or breathing, or widespread muscle weakness, in the days or weeks after toxin

Tell them you have had an injectable, which product, where and when.

CONTACT YOUR INJECTOR IMMEDIATELY

  1. PAINSevere pain, or pain that is getting worse
  2. COLOURSkin that is white, dusky, grey, blue or mottled
  3. TEMPERATUREA patch of skin that feels cold
  4. SKINBlisters or small pus spots

If you cannot reach them within minutes, go to an emergency department. Numbing agents in the filler, or a nerve block, can hide pain, so a colour change matters even if it does not hurt. These signs can appear during treatment or hours to days afterwards. Not every emergency department stocks hyaluronidase or sees these problems often, so tell staff exactly what was injected.

Being the patient who calls and turns out to be fine costs nothing.

Who should not have this, and what to declare.

Some people are not treated, and some need to tell their practitioner first. This list is not complete. A full medical history and medication review before treatment is the expected standard. Treatment is usually avoided in pregnancy and while breastfeeding. Neuromuscular conditions such as myasthenia gravis or Lambert-Eaton syndrome rule out toxin. Aminoglycoside antibiotics and some other medicines can strengthen the effect of toxin. Active skin infection or cold sores at the site mean waiting. Allergy to any ingredient matters, including lidocaine, hyaluronidase or, for Dysport, cow's milk protein. Bleeding disorders and blood thinners raise the risk of bruising. Do not stop prescribed medication without speaking to your doctor. Autoimmune disease, a weakened immune system, keloid scarring, and permanent or unknown filler already in the area all need disclosing. So does recent or planned dental work, vaccination or surgery. Distress about a feature, or a history of body dysmorphic disorder, is part of the assessment. Many countries set a minimum age, and some ban cosmetic toxin and filler for under-18s outright. Rules differ by country and by state.

Counterfeit and unlicensed products

Botulinum toxin is a prescription-only medicine almost everywhere it is legally sold. Fake and unlicensed versions are sold online and used in homes, salons and at parties. They can contain the wrong dose, the wrong substance or contamination. Counterfeit toxin has caused botulism-like illness, with people needing hospital treatment for weakness and trouble swallowing or breathing. Unlicensed fillers carry similar unknowns. Outside a medical setting there may be no prescriber, no hyaluronidase, no adrenaline and no record of what was used. If something goes wrong, nobody may know what you were given.

questions. The answers tell you more than the price does.

You do not need to know anatomy. You need to know whether the person holding the needle does, and what happens on the day something is wrong.

ABOUT THE PRODUCT
  1. What exactly are you injecting, and how much?Your treatment record should show the product name, the batch number, the dose or volume, where it was injected and the date. If you have a reaction, this tells the treating team exactly what they are dealing with. It also allows a faulty or counterfeit batch to be traced and other patients to be contacted. Toxin brands are measured in different units and are not interchangeable, so the brand matters as much as the number of units. A record that leaves out the product or batch is incomplete.
  2. Why that product, and why that depth?A good answer connects your face to a specific plane and a specific cause. A vague one is a warning.
  3. Is this reversible, and what are my options if I do not like it?It depends on the treatment, and reversing a product is not the same as undoing its effects. Toxin cannot be undone and has no antidote. It wears off over months, so unwanted effects are temporary but may last weeks to months. Hyaluronic acid filler can largely be broken down with hyaluronidase. It may take more than one session, some products resist it, the enzyme can cause allergic reactions, and it cannot undo damage that has already happened. It is a safety net, not an eraser. Biostimulators cannot be reliably dissolved. Threads can sometimes be removed, but not always completely. Fat cells destroyed by deoxycholic acid do not return. Permanent fillers may need surgery, and removal may be incomplete.
ABOUT THE BAD DAY
  1. Do you keep hyaluronidase here, in this room?If hyaluronic acid filler is being injected, the answer needs to be yes, without hesitation. Ask about adrenaline too, for severe allergic reactions.
  2. What is your protocol if there is a vascular occlusion?Anyone qualified to inject filler can describe this immediately. Hesitation is your answer.
  3. Who do I call at ten at night, and will a person answer?A number that reaches a human, not a booking form. Ask what they would tell you to do about vision changes.
ABOUT THE PERSON
  1. What is your licence, and what does it permit you to do here?Rules differ by country and by state, and who may inject, and under whose supervision, varies with them.
  2. How many of these do you do in a month?Recent, regular experience with this specific procedure matters, not only years in practice.
  3. What would you not do to my face?Someone who will talk you out of something is worth more than someone who agrees with everything.