Patient Information Leaflet



If you are considering having sclerotherapy for the treatment of unwanted veins, we recommend that you read the following information. This will help you to be fully prepared and know what questions to ask. Prior to treatment, you should have a face-to-face consultation with your treating practitioner and be offered a cooling off period before returning for treatment, so that you have time to consider your decision carefully based on the information you have been provided with and alternative options. You should be advised regarding expected outcomes and any questions you have should be answered. Dependent on the appearance and pattern of your veins, you may be advised to have a scan of your leg prior to treatment to ensure that there are no deep veins feeding the superficial veins visible on the skin. If this is the case, these may need to be treated first for a successful result else you might not achieve your desired outcome or thread veins may recur soon after your procedure.

What is Sclerotherapy?

Prominent leg veins, spider veins and matting are a very common problem that can cause a great deal of distress and embarrassment.  They can affect everyday life, what clothes to buy and dreading the summer holidays! Spider veins are naturally occurring blue or red prominent veins visible in the skin and are a millimetre or so in diameter. They may be caused by the normal ageing process, hormonal changes, prolonged standing or sitting, sun exposure, obesity, injury, and genetics.


Sclerotherapy is a safe and well-established medical procedure used to treat certain types of unwanted veins, primarily varicose veins, and spider veins. It is a minimally invasive treatment that involves the injection of a solution directly into the affected veins, causing them to collapse and eventually fade away. Sclerotherapy is commonly performed on superficial veins near the surface of the skin, such as spider veins and small varicose veins. It is done on an outpatient basis and does not normally require pain relief or analgesia. Multiple treatment sessions may be necessary to achieve optimal results, depending on the extent and severity of the veins being treated.


It is important to note that while sclerotherapy is effective in improving the appearance of varicose and spider veins, it does not prevent the formation of new ones. Additionally, the procedure may not be suitable for everyone, and a consultation with a qualified healthcare professional is recommended to determine the best treatment approach for individual cases.


Make sure you understand why sclerotherapy may be suitable for you, what you can hope to achieve and any alternative treatment options.
Are there any other alternatives to Sclerotherapy?
Sclerotherapy is the gold standard treatment for veins up to 3-4mm in diameter although other options may include transdermal laser, Intense Pulsed Light (IPL) and electrocoagulation whereas veins greater than 4mm, including varicose veins and truncal reflux, are more suited to foam sclerotherapy, endovenous ablation or phlebectomy.
  • Laser Therapy: Laser treatment, such as endovenous laser ablation (EVLA) or laser therapy (EVLT), uses targeted laser energy, which is delivered via a thin fibre-optic laser inserted into the vein via a small incision. This heats and closes off the unwanted veins and is recommended for larger varicose veins.
  • Radiofrequency Ablation: Like laser therapy, radiofrequency ablation (RFA) uses heat to destroy the problematic veins. It involves inserting a catheter into the vein and applying radiofrequency energy to seal it shut.
  • Vein Stripping and Ligation: This is a surgical procedure in which the affected veins are tied off (ligated) and then removed (stripped) through small incisions. Vein stripping is typically reserved for more severe cases of varicose veins and due to the effectiveness of alternative methods with less downtime and lack of scarring, is now performed less frequently.
  • Ambulatory Phlebectomy: Also known as microphlebectomy or stab avulsion, this procedure involves the surgical removal of surface varicose veins through tiny incisions. It is often performed under local anaesthesia and may be combined with other treatments like sclerotherapy.
  • Compression Therapy: Compression stockings or socks are often recommended as a conservative treatment option for mild cases of varicose veins or as a preventive measure. Compression garments help improve circulation and reduce symptoms associated with leg veins.

The choice of treatment depends on various factors, including the size, location, and severity of the veins, as well as the individual’s overall health and preferences. It is essential to consult with a qualified healthcare professional, such as a vascular surgeon or sclerotherapist, who can evaluate your specific condition and recommend the most appropriate treatment approach.

What areas can be treated?

Sclerotherapy is generally performed on the legs for unsightly or unwanted veins, however some specialists may offer treatments in other areas after appropriate examination, such as pelvic and breast veins. Sclerotherapy is not suitable for treating facial veins and your practitioner may recommend either laser treatment or the insertion of a tiny needle to coagulate the veins.


Make sure that the area and concern is suitable for sclerotherapy.
How does Sclerotherapy work?

Sclerotherapy works by causing irritation and inflammation in the targeted blood vessels, leading to their closure and eventual absorption by the body. During sclerotherapy, a sclerosing agent in liquid or foam form, is injected into the targeted veins using a fine needle. The solution irritates the inner lining of the blood vessels, causing inflammation and a series of reactions causing them to stick together and seal shut. Over time, the collapsed veins are reabsorbed by the body and fade from view, improving the appearance of the skin.


The specific sclerosing solution used may vary depending on the practitioner’s preference and the characteristics of the veins being treated. Your healthcare provider will assess your condition and determine the appropriate sclerosing agent and strength for your specific needs. Sclerosants are pharmacological agents and there is a maximum dosage that can be administered during a treatment session. In most cases, both legs can be treated during a single treatment although several treatment sessions may be required. Foam sclerotherapy involves foaming up a liquid sclerosant using air or gas and is more suitable for treating larger varicose veins and may be performed under ultrasound guidance.

Is it painful?

The level of discomfort experienced during sclerotherapy can vary from person to person. People have different pain thresholds and levels of sensitivity and what may be perceived as uncomfortable for one person may be tolerable for another. Sclerotherapy has mostly been described as mild discomfort only. The sclerosant used can also affect the pain during the procedure and this should be discussed at your consultation. Other factors include injection volume and pressure, needle size and the amount of veins present. While sclerotherapy may involve some discomfort, it is generally well-tolerated by most patients. It is important to communicate any discomfort you experience to the healthcare professional performing the procedure. They may be able to adjust their technique or provide additional measures to alleviate any discomfort, such as using a topical anaesthetic or applying cold compresses before the injections.


After the procedure, you may experience some tenderness, bruising, itching or mild swelling at the injection sites. These symptoms are usually temporary and resolve within a few days to weeks. If you have concerns about pain management during sclerotherapy, it is best to discuss them with your healthcare provider beforehand.

Is it safe?

While sclerotherapy is generally considered a safe and effective procedure, there are potential risks and side-effects associated with the treatment and it sensible to discuss them with your healthcare provider before undergoing treatment.


  • Common Side Effects: Following sclerotherapy, it is common to experience mild side effects such as bruising, redness, or swelling at the injection sites. These side effects are typically temporary and resolve on their own within a few days to weeks. Itching and a hive-like rash may occur during treatment due to histamine release caused by the procedure, this will settle quickly without treatment but if it is problematic or persistent, an antihistamine may be recommended.
  • Matting: In some cases, tiny new blood vessels may form near the treated area, a condition known as “matting” or “telangiectatic matting”. This can result in a network of fine red or purple veins in the treated area. Matting can occasionally resolve on its own, but further treatment may be required in some cases.
  • Skin Discolouration: The treated veins may temporarily darken or develop brownish pigmentation. This discoloration usually fades over time, but it may persist for several months. In rare instances, permanent skin discoloration can occur.
  • Discomfort/Pain: Treated veins may ache or be painful following treatment, particularly if you have been standing still for prolonged periods of time. Simple analgesia may be required. If pain is more than expected, you must contact your treating practitioner for further advice.
  • Superficial Phlebitis: Phlebitis is the medical term for inflammation of a vein, which can occur as a potential complication after sclerotherapy. While it is relatively rare, it is important to be aware of the risk. Superficial thrombophlebitis typically presents with localised pain, tenderness, redness, and swelling along the affected vein and the area may feel warm to the touch and appear visibly inflamed.
  • Ulceration and Skin Damage: In rare instances, sclerotherapy may lead to skin ulceration or tissue damage at the injection site. This risk is higher when larger veins are treated or if the sclerosing solution leaks into the surrounding tissues.
  • Incomplete Treatment: Sclerotherapy may not eliminate all veins during a single treatment session, particularly in cases of extensive or complex vein issues. Multiple treatment sessions may be necessary to achieve the desired results.
  • Infection: Whilst rare, there is a small risk of infection at the injection site.
  • Allergic Reaction: Although rare, some individuals may experience an allergic reaction to the sclerosing solution used during the procedure. Symptoms may include itching, rash, hives, difficulty breathing, or swelling. It is important to discuss any known allergies with your healthcare provider prior to the treatment. Suspected allergic reactions following treatment needs urgent medical attention.
  • Headache/Migraine: This is not a commonly reported side-effect, however it may occur following treatment, particularly if you are particularly stressed or anxious pre-treatment.
  • Nerve Injury: The risk of nerve injury during sclerotherapy is generally considered low, but it is a potential complication that should be recognised. Symptoms of nerve injury may include numbness, tingling, altered sensation, pain, or muscle weakness in the area supplied by the affected nerve. If you develop any of these concerns, it is crucial to contact your treating practitioner. Nerve injury following sclerotherapy generally fully recovers over time, but it may take several weeks or months.
  • Blood Clots: While uncommon, the formation of blood clots within the treated veins is a potential risk. Blood clots can cause pain, inflammation, and potentially more serious complications if they travel to other parts of the body. Blood clots can lead to a deep vein thrombus or embolise to cause a heart attack or a stroke.
We recommend that treatments are performed in a suitable clinical environment with sharps disposal.

It is important to have a thorough discussion with your healthcare provider prior to sclerotherapy. They can evaluate your individual situation, discuss potential risks and benefits, and address any concerns you may have. By choosing a skilled and experienced healthcare professional, adverse events and complications can be minimised.


If you develop any unexpected side-effects after treatment, it is important to contact your practitioner for a review as soon as possible, as they may be able to offer some corrective treatment. Although your practitioner may contact you by telephone or video call initially or you may send your own photographs, this is no substitute for a face-to-face review to provide an accurate diagnosis and appropriate management.


Your practitioner  should provide you with an out of hour’s emergency number.
What does the procedure involve?

Prior to your treatment you should receive a full consultation, complete a medical questionnaire, and be offered a cooling off period to enable you to make an informed decision with full disclosure of the possible risks and side effects specific to you. You should also be given an indication of the cost of the treatment. Before you receive any treatment, you will be required to sign a consent form, this may be on paper or electronic, and be given the opportunity to ask any further questions. Photographs may be taken and kept as part of your medical record. These should not be used for any other purpose without your explicit permission.


On the day of the procedure, you should wear loose-fitting and comfortable clothing, preferably shorts or a skirt that can easily expose the treatment area. It is advisable to avoid applying any lotions, oils, or creams to your legs before the procedure. Avoid wearing sandals that fit between the toes as you may not be able to put these on if compression hosiery has been applied. You will be positioned in a way that allows easy access to the treatment area. Typically, you will lie down on an examination table with your legs elevated slightly. The healthcare professional will use a fine needle to inject a sclerosing agent into the targeted veins. Sometimes the practitioner may use additional equipment such as a magnifying lens, Veinlite or ultrasound to improve the visibility of the veins. The practitioner will carefully insert the needle into the affected vein and slowly inject the sclerosing solution. After each injection, gentle compression or massage may be applied to the treated area.


It is important to note that the duration and specifics of the procedure may vary depending on the individual case and the extent of the veins being treated, however a typical treatment may last about 30 minutes. The healthcare professional performing the procedure will provide you with detailed instructions and answer any questions you may have before the treatment begins.


Do not feel pressurised or coerced into having treatment at the same time as your consultation.


Am I suitable for treatment?
  • Sclerotherapy is not recommended during pregnancy or breast-feeding nor if you are actively trying to get pregnant or undergoing IVF.
  • Individuals with a history of deep vein thrombosis, pulmonary embolism or blood clotting disorders may be at an increased risk of developing blood clots after sclerotherapy.
  • If you have an active infection in the treatment area or a systemic infection, sclerotherapy should be postponed until the infection is fully resolved. Treating an infected area can increase the risk of spreading the infection or interfering with the healing process.
  • If you have a known allergy or hypersensitivity to the sclerosing solution used in sclerotherapy, the procedure should be avoided.
  • If you suffer from any impaired mobility. Sclerotherapy requires you to maintain certain positions and follow post-procedure activity recommendations. If you have impaired mobility or are unable to follow these instructions, it may impact the success and safety of the procedure.
  • If you have certain medical conditions, such as diabetes, rheumatoid arthritis, autoimmune conditions, cancer, immunosuppression (either medical or drug-related).
  • If you are unwell, including coughs and colds, on the day of treatment.
  • If you are taking any medicines which affect bleeding, such as aspirin or warfarin.
It is important to be honest about your medical history, previous surgery and any medication taken so that you can have a safe and effective treatment.
Pre-treatment advice
  • Avoid taking anti-inflammatories (such as aspirin, ibuprofen or naproxen) for 3 days prior to treatment (unless this has been prescribed by your doctor) as this increases the risk of bruising.
  • Alcohol, fish oils, St. John’s Wort, Gingko Biloba and Vitamin E should also be avoided for 3 days prior to treatment to lessen the risk of bruising.
  • If you are prone to bruising, taking arnica orally for a few days prior to treatment may lessen the risk.
  • If you are unwell on the day of your appointment, contact the practitioner to reschedule.
  • Avoid sunbeds and tanning for 1 week before and after treatment.
  • Ensure your practitioner is informed if there are any changes in your medical history or medication taken before receiving any treatment.
Post-treatment advice

After undergoing sclerotherapy, it is important to follow the post-treatment advice to promote healing, minimise potential complications and to optimise the results of the procedure.


  • Your practitioner may recommend wearing compression stockings or bandages following treatment. Compression helps promote blood flow, reduces swelling, and can help with the effectiveness of treatment and limit complications.
  • Engage in light walking and regular physical activity after sclerotherapy. This helps promote circulation and prevent blood clots from forming and it is often recommended to go for a short walk immediately after treatment. However, avoid strenuous exercise or activities that put excessive strain on the treated area for the period recommended by your healthcare provider.
  • Protect the treated area from direct sun exposure for a few weeks after sclerotherapy. Ultraviolet (UV) radiation can increase the risk of skin discoloration and interfere with the healing process. If sun exposure is unavoidable, use a broad-spectrum sunscreen with a high SPF and apply it generously to the treated area.
  • For a few days after the procedure, avoid hot baths, hot tubs, saunas, or any activities that expose the treated area to excessive heat.
  • Discuss with your practitioner whether it is safe to resume any medications or supplements that were temporarily discontinued before the procedure.
  • Attend any scheduled follow-up appointments with your healthcare provider. They will assess your progress, monitor the healing process, and determine if additional treatment sessions are required.
  • If you experience persistent pain, increasing swelling, redness, warmth, or signs of infection at the treatment site, notify your healthcare provider promptly. These could be signs of complications that require medical attention.

Understand that the full results of sclerotherapy may take time to be visible. It may take several weeks to months for the treated veins to fade and for you to see the desired improvement. Be patient and realistic about the outcome.

Choosing your practitioner

Ensure you know the following information:


  • Practitioner’s/therapist’s full name
  • Practitioner’s/therapist’s profession/qualifications
  • Practitioner’s/therapist’s contact details (address, telephone number, and email)
  • An emergency contact number in case a complication occurs.

Practitioners should be registered with a professional body (General Medical Council, General Dental Council, Nursing and Midwifery Council, General Pharmaceutical Council or Health and Care Professions Council) and you can check their current registration status online.


Practitioners are accountable to these bodies and are legally required to have indemnity insurance in place for all the treatments they perform.

If you are not happy with your treatment outcome, you should attempt to resolve this with your treating practitioner in the first instance. If you need to see a different practitioner, you are entitled to receive a copy of your treatment record outlining the product used and areas and volumes injected, to have your concerns addressed safely. However, remedial treatment may not always be possible.


The ACE Group World patient leaflets have been produced to give you some ideas of what the treatment involves, possible side effects, what you should expect and what you should ask.

Patient Leaflets

Purchase Patient Information Leaflets to use in your own practice.