PDO threads: risks and what can go wrong
PDO threads have expected side effects (pain when moving the face, a pulling sensation, swelling and bruising in the first days) and less common complications: dimples that persist, asymmetry, a palpable or visible thread, the thread coming out through the skin (extrusion) and infection. Nerve and salivary gland injuries are rare, but must be included in the consent. Many of these situations have a management plan, and most frustrations come from an expectation of a surgical lift, not from a complication.
This page organizes the risks at a review level, so you can explain them to the patient at the assessment and recognize early when something is not going well. Detailed clinical management is in complications with PDO threads.
Expected effect or complication?
Separating the two is what reassures the patient most afterward:
| Expected in the first days | Calls for assessment |
|---|---|
| Pain when opening the mouth, smiling or chewing | Pain that increases after the third day |
| Swelling and a pulling sensation | Hardened, warm swelling with redness |
| Bruise or ecchymosis that changes color | A bruise that grows in size or hardens |
| Small dimples or ripples | A deep dimple that does not improve in two weeks |
| A feeling of the thread when pressing the area | Thread tip visible or coming out through the skin |
| Slight difference between the sides | Evident facial asymmetry once the swelling has gone down |
The expected recovery, day by day, is in PDO threads: pain, swelling and bruising.
What complications can occur?
| Complication | How it usually appears | What is usually done |
|---|---|---|
| Dimples and irregularities | Depressions or ripples in the skin, especially when smiling | Many improve in days to weeks; persistent ones are assessed by the professional |
| Asymmetry | One side pulled more or with a different result | Assessment after the swelling; adjustment as needed |
| Palpable or visible thread | A cord felt to the touch or seen under thin skin | Observation or removal, at the professional's discretion |
| Extrusion | Thread tip showing through the skin or mucosa | Assessment; usually removal of the exposed segment |
| Infection | Pain, warmth, redness, discharge, sometimes weeks later | Same-day assessment and treatment as appropriate |
| Inflammatory reaction and granuloma | Persistent nodule along the thread | Assessment; management according to the diagnosis |
| Nerve injury | Altered sensation (paresthesia) or movement | Assessment; often temporary, but requires follow-up |
| Salivary gland injury | Swelling on the side of the face related to eating | Specialist assessment |
| Result below expectations | "Nothing changed" after the swelling | Review the indication and expectations; combine other approaches |
Why does infection deserve special attention?
A thread is a foreign body that stays in the tissue for months. Bacteria that enter through the insertion point can form biofilm around it, which explains infections that appear late and respond worse to treatment. Rigorous asepsis, proper technique and guidance not to manipulate the area in the first days are the most cited preventive measures. Room setup is covered in biosafety in HOF.
What increases the risk?
- Wrong indication: marked laxity, very thin or very heavy skin, expectation of a surgical lift. See do PDO threads work?.
- Thin skin: the thread is easier to feel and see.
- Intense movement in the first days: favors displacement and dimples.
- Clinical conditions and medications that affect healing or clotting, identified in the medical history.
- Facial procedures with pressure or devices on the area right afterward.
When the thread "went wrong": what can be done?
The honest answer is that it depends on the problem. A mild irregularity usually settles with time. An exposed thread, infection, persistent nodule and significant asymmetry are assessed by the professional, who decides between observing, treating clinically or removing the thread, when possible. Unlike hyaluronic acid, a thread cannot be undone with an enzyme; it is absorbed gradually over months. The comparison is in PDO threads or hyaluronic acid.
How do you reduce risks in practice?
- Indicate for the right profile and record the agreed expectation.
- Take standardized photos beforehand: front, profile and three-quarter.
- Explain the expected effects and complications in the informed consent; there is a consent form template for PDO threads.
- Hand over written instructions, with warning signs and a contact channel; see the post-thread instructions template.
- Schedule a follow-up and record everything in the patient record, including the product lot.
An overview of the risks of aesthetic facial procedures, for those comparing options, is in does facial harmonization have risks?.
Where does Harmy fit in?
Harmy does not simulate threads. In the consultation, the projection works with volume in the marked areas, which helps separate what is a volume concern from what is laxity. In follow-up, "Add actual result" stores the follow-up photo aligned with the before photo, useful for documenting progress.
Frequently asked questions
What are the risks of PDO threads?
The most common are pain, swelling, bruising and small irregularities in the first days. Less common are persistent dimples, asymmetry, a palpable or visible thread, the thread coming out through the skin (extrusion) and infection. Nerve and gland injuries are rare.
Can a PDO thread go wrong?
It can, like any procedure. The most reported problems are irregularities, asymmetry and a visible thread, which often improve with time or with the professional's management. Expecting a surgical lift also creates the feeling that it went wrong.
What are the side effects of PDO threads?
Pain when moving the face, a pulling sensation, swelling, bruising and tenderness in the first days are the expected side effects. They usually improve within one to two weeks.
Is there a fix for a PDO thread that went wrong?
Many complications have a management plan: mild irregularities tend to settle, and an exposed thread, infection or significant asymmetry are assessed by the professional, who may indicate clinical treatment or thread removal in specific situations.
Harmy images are illustrative simulations generated by AI from the patient's photo to support the conversation between practitioner and patient. They are not a promise of results. Indication, technique, product and volume are solely the decision of the licensed practitioner. This content is for information only and does not replace a clinical assessment.