Both unfractionated heparin (UFH) and low molecular weight heparins (LMWHs, like enoxaparin) work by activating antithrombin, which then inhibits clotting factors. However, the size of the molecules leads to a key difference in their primary target. UFH molecules are long and can bridge antithrombin to both thrombin (Factor IIa) and Factor Xa, inhibiting them equally. LMWHs are shorter molecules. They are too short to bridge antithrombin to thrombin effectively, but they can still bind and enhance antithrombin's inhibition of Factor Xa. Therefore, LMWHs have a much higher anti-Factor Xa activity compared to anti-Factor IIa activity. This more predictable activity contributes to LMWH's advantages: more predictable dosing without routine monitoring, a longer half-life, and a lower risk of heparin-induced thrombocytopenia (HIT).

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Zambia

• Naomi Miselo – 31 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies