Thursday, 10 November 2016

Drugs affecting fibrinolysis
Classification
        I.            Fibrinilytic drugs
a)     Direct-acting: Fibrinolysin
b)     Indirect-acting (activators of profibrinolysin)
a)     Non-selective: Streptokinase, Streptoliase
b)     Selective: Alteplase
      II.            Inhibitors of fibrinolysis
a)     Direct –acting: Contrical
b)     Indirect- acting: Aminocaproic acid,  Amben

FIBRINOLYSIN
It is protein from donors’ plasma, the active factor of fibrinolysis & administered by IV infusion. It has direct action on fibrin and dissolves fibrin clot in the first hours after thrombosis. It is used for treatment of acute thrombosis, acute miocardial infarction, thrombophlebitis. It may cause bleeding resulting from increase in fibrinilysis, allergy, anaphylaxis, arrythmia, hypotension.


Contraindications: bleeding, cerebral vascular accident, recent trauma of brain, surgery, uncontrolled hypertension.

activators of fibrinolysis
steptokinase
It is the proteolytic enzyme from haemolytic streptococcus. It acts indirectly, inhibits the conversion of plasminogen to plasmin & degradation both of fibrin and fibrinogen to systemic activation of fibrinolysis and dissolving of thrombus.  Plasma half-life is 23 min; is administered by IV infusion (intracoronary infusion in myocardial infarction). It is more active than fibrinolysin, does not cause arrhythmia.
Alteplase (ACTILISE)
It is tissue plasminogen activator, product of biotechnology, half-life is 5 min& is administered by IV infusion. It has high affinity for fibrin and selectively acts only on plasminogen, bound with thrombus.

Inhibitors of fibrinolysis
Contrical (Aprotinin)
It is direct acting inhibitor of fibrinolysis and proteolysis & administered IV slowly or by IV infusion.It binds with plasmin and inactivates it, inhibits activity of trypsin and kallikrein. It inhibits fibrinilysis and decreases bleeding caused by activation of fibrinolysis; inhibits proteolysis and inflammation.
indications: bleeding resulting from activation of proteolysis, myocardial infarction, acute pancreatitis, prophylaxis of proteolytic complications after surgeries on pancreas, thyroid glands, prevention of proteolysis activation after the surgery on bigger salivary glands; paradontitis (topically)
 Side-effects: allergy, nausea, vomiting, hypotension, tachycardia
Aminocaproic acid
It  is indirect-acting inhibitor of fibrinolysis & administered orally and by IV infusion, acts during 4-6 hr, is not metabolized and excreted with urine.It  interacts with plasminogen and inhibits its transformation into plasmin, particularly inhibits plasmin; inhibits proteolytic enzymes and kallikrein. It inhibits fibrinolysis and decreases bleeding caused by the activation of fibrinolysis; suppresses proteolysis, decreases inflammation, has anti-allergic action, stimulates antitoxic function of the liver.
Indications: They are similar to the same to contrykal and also syndrome of dessemenated intranasal blood coagulation, obstetrics pathology (ablation placenta, uterine haemorrhages), liver diseases, hypoplastic anaemia.It is use in dentistry is applied topically to treat parodontitis and to stop bleeding from dental root channels.
Side-effects: Dizziness, hypotension, bradycardia, arrhythmia, skin rash, vomiting , nausea.

No comments:

Post a Comment