Pharmacology Dvt In the Legs There Are Term Paper

Excerpt from Term Paper :



In the legs, there are two kinds of veins, namely, deep and superficial. The deep veins pass through the middle of the leg, enclosed by the muscles. A blood clot or thrombus that crops up in the deep veins of the leg is called a Deep Vein Thrombosis or DVT. Blood clot, and hence DVT, can arise due to slowing down or stoppage of blood or due to damage of the vein. DVT produces pain in the leg, and can result in complications if it breaks off and travels in the bloodstream to the lungs. Occasionally, DVT can take place in the deep veins of the arm or pelvis. The incidence of DVT is more probable for people with following conditions: age above 40, obesity and previous history of DVT. Other factors that lead to DVT are: extended bed rest or serenity; major impairments or paralysis; surgery, particularly if it extends more than 30 minutes or includes the leg joints or pelvis; cancer and its treatments that can lead the blood to clot more easily; long-distance travel due to long-drawn-out stillness. (Deep vein thrombosis: BUPA's Health Information Team)

It is not clear whether long-distance travel by car or coach is risky or long-distance travel by air is risky. During pregnancy and childbirth, the blood clots more easily due to hormone changes and due to the fact that the fetus puts added pressure on the veins of the pelvis. During delivery or a caesarean, there is yet another threat of damage to veins, the threat being highest just after childbirth. A DVT below the knee is not likely to result in difficulties and may only have to be monitored. However, when a clot forms in or above the knee, there is a danger that it will split away and travel up the vein to obstruct a blood vessel in the lung. This is called a Pulmonary Embolism or PE. Based on the dimensions of the clot, it can be a critical condition. But with suitable treatment, it is unusual for a DVT to result in a pulmonary embolism. A DVT can harm the valves in the vein, so that as opposed to flowing upwards, the blood pools in the lower leg. This is called post-thrombotic syndrome, and can lead to pain, inflammation, staining and sores on the leg. (Deep vein thrombosis: BUPA's Health Information Team)

Treating DVT using Lovenox:

DVT treatment aims at putting a stop to the growth of a pulmonary embolus and at averting periodic DVT. The popular treatment for DVT for many years has been an anticoagulant medication called heparin and heparin was administered through the vein. Heparin so applied lead to somewhat instant anticoagulation and treatment of the clot. In addition to heparin, warfarin, an oral medication, is given. As warfarin generally takes many days to attain usefulness or a therapeutic level, the heparin is continued. Heparin is stopped after the warfarin attains therapeutic level for a minimum duration of 24 hours. Thereafter, warfarin is generally continued for about six months even though there is some deliberation about the most favorable duration of therapy. In any case, warfarin should not be commenced until heparin has been started. As heparin is given as an incessant intravenous infusion, it necessitates hospitalization. Nevertheless, latest types of heparin called Low Molecular Weight Heparin or LMWH can be used in some situations. The well-known LMWH is enoxaparin. This heparin can be given by injection once or twice a day and thus can cut down or get rid of the need for hospitalization. (Deep venous thrombosis: Medical Encyclopedia)

The distinctive biology of the compound heparin is not well understood by the nurses who are otherwise familiar with the property of anticoagulation produced by it. Heparin is a molecule with many varied functions, and research continues into details of its anticoagulant function as well as supplementary cellular roles that are not evidently understood. Heparin is traditionally administered as un-fractionated heparin or UH, a heterogeneous mixture. Heparin is now available in more homogeneous preparations that have varied acts and pharmaco-kinetics. Major benefits of low-molecular-weight heparins or LMWHs are enhanced bioavailability and expanded half-life, more foreseeable anticoagulation that necessitates less laboratory monitoring, and less serious side effects. Enoxaparin (Lovenox) is, at present, the most extensively used LMWHs. (Gylys, 2001)

Pharmacodynamic effects of Lovenox used for treating DVT:

Lovenox Injection is a sterilized aqueous solution having enoxaparin sodium which is also a low molecular weight heparin. Lovenox Injection is accessible in two concentrations like: 100 mg per ml and 150 mg per ml. Enoxaparin is a low molecular weight heparin, and it has antithrombotic properties. In humans, enoxaparin provided at a dose of 1.5 mg/kg subcutaneous is depicted by an elevated ratio of anti-Factor Xa to anti-Factor IIa activity in comparison to the ratios detected for heparin. The control values were observed in the thrombin time or TT at an enhancement of up to 1.8 times and the stimulated partial thromboplastin time or aPTT. Enoxaparin at a 1-mg/kg dose with SC given to patients every 12 hours in a large clinical trial ended in aPTT values of 45 seconds or less in most of the patients. (Lovenox (enoxaparin sodium injection)

Pharmacokinetics study done using 100 mg / ml concentration showed Absorption. Highest anti-Factor Xa and anti-thrombin activities take place of about 3 to 5 hours after SC injection of enoxaparin. Average peak anti-Factor Xa activity was 0.16 IU/ml and 0.38 IU/ml after the 20 mg and the 40 mg clinically tested SC doses, correspondingly. Mean peak anti-Factor Xa activity was 1.1 IU/ml at stable state in patients with uneven angina receiving 1 mg/kg SC every 12 hours for 14 days. Mean complete bioavailability of enoxaparin, after 1.5 mg/kg given SC, on the basis of an anti-Factor Xa activity is about 100% in healthy partners. Enoxaparin pharmacokinetics seems to be linear over the suggested dosage limit. After continuous subcutaneous dispensing of 40 mg once daily and 1.5 mg/kg once-daily routines in healthy people, the steady state is attained on day 2 with an average exposure ratio about 15% greater than after a single dose.

Stabilized enoxaparin activity levels are well expected by single-dose pharmacokinetics. After continuous subcutaneous administration of the 1 mg/kg twice daily regimen, the balanced state is attained from day 4 with mean exposure about 65% higher than after consuming a single dose and mean peak and trough levels of about 1.2 and 0.52 IU/ml, correspondingly. This variation in steady state is anticipated and is found in the remedial range which is focused on enoxaparin sodium pharmacokinetics. Though it has not been examined clinically, the 150-mg/ml concentration of enoxaparin sodium is expected to effect in anticoagulant activities, which are comparable to those of 100 mg/ml and 200 mg/ml concentrations at the same enoxaparin dose. (Lovenox (enoxaparin sodium injection)

In the March 14th 1996 issue of The New England Journal of Medicine, the results of a clinical test was published, which showed that patients with possible serious blood clots can be cured with Lovernox or enoxaparin sodium, which removes the requirement for hospitalization or greatly minimizes hospital stays, raising the patient expediency and possibly preventing large health-care expenses. A Canadian study was done on 500 patients. To cure patients with severe proximal deep vein thrombosis or DVT, patients were injected with Lovenox LMWH in the home atmosphere and were evaluated with those to standard intravenous heparin given in the hospital. Mark N. Levine, main author of the study and CEO of the Hamilton Regional Cancer Center said that the results of this test have proved that low molecular weight heparin is helpful for home use. Due of its exclusive pharmacological properties and more expected anticoagulant reactions; low molecular weight heparin like enoxaparin has the benefit of permitting DVT to be cured in the home setting…

Cite This Term Paper:

"Pharmacology Dvt In The Legs There Are" (2005, July 28) Retrieved January 23, 2018, from

"Pharmacology Dvt In The Legs There Are" 28 July 2005. Web.23 January. 2018. <>

"Pharmacology Dvt In The Legs There Are", 28 July 2005, Accessed.23 January. 2018,