Treatment can be either conservative or active. Active treatments can be divided into surgical and non-surgical treatments. Newer methods including endovenous laser treatment, radiofrequency ablation and foam sclerotherapy appear to work as well as surgery for varices of the greater saphenous vein.

The National Institute for Health and Clinical Excellence (NICE) produced clinical guidelines in July 2013 recommending that all people with symptomatic varicose veins (C2S) and worse should be referred to a vascular service for treatment. Conservative treatments such as support stockings should not be used unless treatment was not possible.

The symptoms of varicose veins can be controlled to an extent with the following:

- Elevating the legs often provides temporary symptomatic relief.

- Advice about regular exercise sounds sensible but is not supported by any evidence.

- The wearing of graduated compression stockings with variable pressure gradients (Class II or III) has been shown to correct the swelling, nutritional exchange, and improve the microcirculation in legs affected by varicose veins. They also often provide relief from the discomfort associated with this disease. Caution should be exercised in their use in patients with concurrent peripheral arterial disease.

- The wearing of intermittent pneumatic compression devices have been shown to reduce swelling and increase circulation

- Diosmin/hesperidin and other flavonoids.

- Anti-inflammatory medication such as ibuprofen or aspirin can be used as part of treatment for superficial thrombophlebitis along with graduated compression hosiery – but there is a risk of intestinal bleeding. In extensive superficial thrombophlebitis, consideration should be given to anti-coagulation, thrombectomy, or sclerotherapy of the involved vein.

- Topical gel application helps in managing symptoms related to varicose veins such as inflammation, pain, swelling, itching, and dryness.

Prevention of PTS begins with prevention of initial and recurrent DVT. For people hospitalized at high-risk of DVT, prevention methods may include early ambulation, use of compression stockings or electrostimulation devices, and/or anticoagulant medications.

Increasingly, catheter-directed thrombolysis has been employed. This is a procedure in which interventional radiology will break up a clot using a variety of methods.

For people who have already had a single DVT event, the best way to prevent a second DVT is appropriate anticoagulation therapy.

A second prevention approach may be weight loss for those who are overweight or obese. Increased weight can put more stress and pressure on leg veins, and can predispose patients to developing PTS.

The field of PTS still holds many unanswered questions that are important targets for more research. Those include

- Fully defining the pathophysiology of PTS, including the role of inflammation and residual thrombus after completion of an appropriate duration of anticoagulant therapy

- Developing a PTS risk prediction model

- Role of thrombolytic ("clot-busting") drugs in PTS prevention

- Defining the true efficacy of elastic compression stockings for PTS prevention (and if effective, elucidating the minimum compression strength necessary and the optimal timing and duration of compression therapy)

- Whether PTS prevention methods are necessary for patients with asymptomatic or distal DVT

- Additional treatment options for PTS with demonstrated safety and efficacy (compression and pharmacologic therapies)

Conservative treatment of CVI in the leg involves symptomatic treatment and efforts to prevent the condition from getting worse instead of effecting a cure. This may include

- Manual compression lymphatic massage therapy

- Skin lubrication

- Sequential compression pump

- Ankle pump

- Compression stockings

- Blood pressure medicine

- Frequent periods of rest elevating the legs above the heart level

- Tilting the bed so that the feet are above the heart. This may be achieved by using a 20 cm (7-inch) bed wedge or sleeping in a 6 degree Trendelenburg position. Obese or pregnant patients might be advised by their physicians to forgo the tilted bed.

The current ‘best’ practice in the UK is to treat the underlying venous reflux once an ulcer has healed. It is questionable as to whether endovenous treatment should be offered before ulcer healing, as current evidence would not support this approach as standard care. EVRA (Early Venous Reflux Ablation) ulcer trial - A UK NIHR HTA funded randomised clinical trial to compare early versus delayed endovenous treatment of superficial venous reflux in patients with chronic venous ulceration opened for recruitment in October 2013. The study hopes to show an increase in healing rates from 60% to 75% at 24 weeks.

Research from the University of Surrey and funded by the Leg Ulcer Charity is currently looking at the psychological impact of having a leg ulcer, on the relatives and friends of the affected person, and the influence of treatment.

Venous Insufficiency Conservative, Hemodynamic and Ambulatory treatment" is an ultrasound guided, minimally invasive surgery strategic for the treatment of varicose veins, performed under local anaesthetic. CHIVA is an abbreviation from the French "Cure Conservatrice et Hemodynamique de l'Insufficience Veineuse en Ambulatoire".

Venous ulcers are costly to treat, and there is a significant chance that they will recur after healing; one study found that up to 48% of venous ulcers had recurred by the fifth year after healing. However treatment with local anaesthetic endovenous techniques suggests a reduction of this high recurrence rate is possible.

Without proper care, the ulcer may get infected leading to cellulitis or gangrene and eventually may need amputation of the part of limb in future.

Some topical drugs used to treat venous ulcer may cause venous eczema.

Preventing the development of blood clots in the upper extremities is done by accessing the risk of the development of such clots.The traditional treatment for thrombosis is the same as for a lower extremity DVT, and involves systemic anticoagulation to prevent a pulmonary embolus. Some have also recommended thrombolysis with catheter directed alteplase. If there is thoracic outlet syndrome or other anatomical cause then surgery can be considered to correct the underlying defect.

The 2012 ACCP guidelines offered weak recommendations. For at-risk long-haul travelers—those with "previous VTE, recent surgery or trauma, active malignancy, pregnancy, estrogen use, advanced age, limited mobility, severe obesity, or known thrombophilic disorder"—suggestions included calf exercises, frequent walking, and aisle seating in airplanes to ease walking. The use of graduated compression stockings that fit below the knee and give 15–30 mm Hg of pressure to the ankle was suggested, while aspirin or anticoagulants were not. Compression stockings have sharply reduced the levels of asymptomatic DVT in airline passengers, but the effect on symptomatic VTE is unknown, as none of the individuals studied developed symptomatic VTE.

In terms of treatment for this condition the individual may be advised to do the following: "raise" the affected area to decrease swelling, and relieve pressure off of the affected area so it will encounter less pain. In certain circumstances drainage of the clot might be an option. In general, treatment may include the following:

Venous stasis, or venostasis, is a condition of slow blood flow in the veins, usually of the legs. Venous stasis is a risk factor for forming blood clots in veins (venous thrombosis), as with the deep veins of the legs (deep vein thrombosis or DVT). Causes of venous stasis include long periods of immobility that can be encountered from driving, flying, bed rest/hospitalization, or having an orthopedic cast. Recommendations by clinicians to reduce venous stasis and DVT/PE often encourage increasing walking, calf exercises, and intermittent pneumatic compression when possible.

Prevention is possible with Thrombosis prophylaxis methods and practices.

Treatment usually consists of NSAIDs, such as ibuprofen and local compression (e.g., by compression stockings or a compress). If the phlebitis is associated with local bacterial infection, antibiotics may be used.

For acute infusion superficial thrombophlebitis, not enough evidence exists as of 2015 to determine treatment.

Major orthopedic surgery—total hip replacement, total knee replacement, or hip fracture surgery—has a high risk of causing VTE. If prophylaxis is not used after these surgeries, symptomatic VTE has about a 4% chance of developing within 35 days. Options for VTE prevention in people follow nonorthopedic surgery include early walking, mechanical prophylaxis (intermittent pneumatic compression or graduated compression stockings), and drugs (low-molecular-weight heparin and low-dose-unfractionated heparin) depending upon the risk of VTE, risk of major bleeding, and person's preferences. Following major orthopedic surgery, the ACCP recommends treatment with drugs that reduce the risk of clots (such as fondaparinux and aspirin) with low-molecular-weight heparin (LMWH) suggested as a preference. Intermittent pneumatic compression is also an option. Graduated compression stockings are effective after both general and orthopedic surgery.

Prevention consists of walking, drinking fluids and if currently hospitalized, changing of IV lines. Walking is especially suggested after a long period seated, particularly when one travels.

Treatment may consist of topical applications of steroid based creams and the use of compression stockings to help force the underlying buildup of fluids back out of the lower leg or intermittent pneumatic compression pumps.

The condition is named after two men. James Paget first proposed the idea of venous thrombosis causing upper extremity pain and swelling, and Leopold von Schrötter later linked the clinical syndrome to thrombosis of the axillary and subclavian veins.

Evidence supports the use of heparin in people following surgery who have a high risk of thrombosis to reduce the risk of DVTs; however, the effect on PEs or overall mortality is not known. In hospitalized non-surgical patients, mortality decreased but not statistically significant. It does not appear however to decrease the rate of symptomatic DVTs. Using both heparin and compression stockings appears better than either one alone in reducing the rate of DVT.

In hospitalized people who have had a stroke and not had surgery, mechanical measures (compression stockings) resulted in skin damage and no clinical improvement. Data on the effectiveness of compression stockings among hospitalized non-surgical patients without stroke is scarce.

The American College of Physicians (ACP) gave three strong recommendations with moderate quality evidence on VTE prevention in non-surgical patients: that hospitalized patients be assessed for their risk of thromboembolism and bleeding before prophylaxis (prevention); that heparin or a related drug is used if potential benefits are thought to outweigh potential harms; and that graduated compression stockings not be used. As an ACP policy implication, the guideline stated a lack of support for any performance measures that incentivize physicians to apply universal prophylaxis without regard to the risks. Goldhaber recommends that people should be assessed at their hospital discharge for persistent high-risk of venous thrombosis, and that people who adopt a heart-healthy lifestyle might lower their risk of venous thrombosis.

In those with cancer who are still walking about yet receiving chemotherapy, LMWH decreases the risk of VTE. Due to potential concerns of bleeding its routine use is not recommended. For people who are having surgery for cancer, it is recommended that they receive anticoagulation therapy (preferably LMWH) in order to prevent a VTE. LMWH is recommended for at least 7–10 days following cancer surgery, and for one month following surgery for people who have a high risk of VTEs.

In adults who have had their lower leg casted or placed in a brace for more than a week, LMWH decreased the risk of VTEs. LMWH is recommended for adults not in hospital with an above-knee cast and a below-knee cast, and is safe for this indication.

Following the completion of warfarin in those with prior VTE, long term aspirin is beneficial.

Evidence-based clinical guidelines were published in 2016 for the treatment of VTE.

Before any treatment of leg telangectasia (spider veins) is considered, it is essential to have duplex ultrasonography, the test that has replaced Doppler ultrasound. The reason for this is that there is a clear association between leg telangectasia (spider veins) and underlying venous reflux. Research has shown that 88-89% of women with telangectasia (spider veins) have refluxing reticular veins close, and 15% have incompetent perforator veins nearby. As such, it is essential to both find and treat underlying venous reflux before considering any treatment at all.

Sclerotherapy is the "gold standard" and is preferred over laser for eliminating telangiectasiae and smaller varicose leg veins. A sclerosant medication is injected into the diseased vein so it hardens and eventually shrinks away. Recent evidence with foam sclerotherapy shows that the foam containing the irritating sclerosant quickly appears in the patient's heart and lungs, and then in some cases travels through a patent foramen ovale to the brain. This has led to concerns about the safety of sclerotherapy for telangectasias and spider veins.

In some cases stroke and transient ischemic attacks have occurred after sclerotherapy. Varicose veins and reticular veins are often treated before treating telangiectasia, although treatment of these larger veins in advance of sclerotherapy for telangiectasia may not guarantee better results. Varicose veins can be treated with foam sclerotherapy, endovenous laser treatment, radiofrequency ablation, or open surgery. The biggest risk, however, seems to occur with sclerotherapy, especially in terms of systemic risk of DVT, pulmonary embolism, and stroke.

Other issues which arise with the use of sclerotherapy to treat spider veins are staining, shadowing, telangetatic matting, and ulceration. In addition, incompleteness of therapy is common, requiring multiple treatment sessions.

Telangiectasias on the face are often treated with a laser. Laser therapy uses a light beam that is pulsed onto the veins in order to seal them off, causing them to dissolve. These light-based treatments require adequate heating of the veins. These treatments can result in the destruction of sweat glands, and the risk increases with the number of treatments.

A vein disorder is a class of disease involving veins of the circulatory system.

Common vein disorders include:

- Varicose veins

- Deep vein thrombosis

Phlebitis is typically caused by local trauma to a vein, usually from the insertion of an intravenous catheter. However, it can also occur due to a complication of connective tissue disorders such as lupus, or of pancreatic, breast, or ovarian cancers. Phlebitis can also result from certain medications and drugs that irritate the veins, such as desomorphine.

Superficial phlebitis often presents as an early sign in thromboangiitis obliterans (Buerger's disease), a vasculitis that affects small and medium-sized arteries and veins in distal extremities often associated with cigarette smoking.

Collapsed veins are a common result of chronic use of intravenous injections. They are particularly common where injecting conditions are less than ideal, such as in the context of drug abuse.

Veins may become temporarily blocked if the internal lining of the vein swells in response to repeated injury or irritation. This may be caused by the needle, the substance injected, or donating plasma. Once the swelling subsides, the circulation will often become re-established.

Permanent vein collapse occurs as a consequence of:

- Long-term injecting

- Repeated injections, especially with blunt needles

- Poor technique

- Injection of substances which irritate the veins; in particular, injection of liquid methadone intended for oral use.

Smaller veins may collapse as a consequence of too much suction being used when pulling back against the plunger of the syringe to check that the needle is in the vein. This will pull the sides of the vein together and, especially if they are inflamed, they may stick together causing the vein to block. Removing the needle too quickly after injecting can have a similar effect.

Collapsed veins may never recover. Many smaller veins are created by the body to circulate the blood, but they are not adequate for injections or IVs.

In ideal circumstances, patients with known varices should receive treatment to reduce their risk of bleeding. The non-selective β-blockers (e.g., propranolol, timolol or nadolol) and nitrates (e.g., isosorbide mononitrate (IMN) have been evaluated for secondary prophylaxis. Non-selective β-blockers (but not cardioselective β-blockers like atenolol) are preferred because they decrease both cardiac output by β blockade and splanchnic blood flow by blocking vasodilating β receptors at splanchnic vasculature. The effectiveness of this treatment has been shown by a number of different studies.

However, non-selective β-blockers do not prevent the "formation" of esophageal varices.

When medical contraindications to beta-blockers exist, such as significant reactive airway disease, then treatment with prophylactic endoscopic variceal ligation is often performed.

Some malignancies, especially gliomas (25%), as well as adenocarcinomas of the pancreas and lung, are associated with hypercoagulability (the tendency to form blood clots) for reasons that are incompletely understood, but may be related to factors secreted by the tumors, in particular a circulating pool of cell-derived tissue factor-containing microvesicles. Some adenocarcinomas secrete mucin that can interact with selectin found on platelets, thereby causing small clots to form.

In patients with malignancy-associated hypercoagulable states, the blood may spontaneously form clots in the portal vessels, the deep veins of the extremities (such as the leg), or the superficial veins anywhere on the body. These clots present as visibly swollen blood vessels (thrombophlebitis), especially the veins, or as intermittent pain in the affected areas.