PHARMACOKINETICS
Absorption: approximately 30 to 50% of the ingested dose and bioavailability is not affected by food intake.
Volume of distribution: 9 to 12 L
Protein binding: about 3%
Metabolism: only a small fraction of the drug is metabolized (less than 5%)
Route of elimination: Urinary excretion is the main route of elimination via glomerular filtration.
Half life: 3 hours
Clearance: 110 - 116 mL/min

PHARMACODYNAMIC
Tranexamic acid is antifibrinolytic hemostatic agent that binds to plasminogen and exerts effects on pigmentation via its inhibitory effects on UV light–induced plasminogen activator and plasmin activity. By inhibiting plasminogen activation, tranexamic acid mitigates UV radiation–induced melanogenesis and neovascularization.

Melasma: the recommended dose is 250mg twice daily
Angioedema
Urticaria

Nausea
Vomiting
Diarrhoea
Muscle pain
Hives
Rash
Itching
Difficulty breathing or swallowing

Concomitant use of Tranexamic with Factor IX complex concentrates, anti-inhibitor coagulant concentrates or all-trans retinoic acid (oral tretinoin) may increase the risk of thrombosis. Visual or ocular adverse effects may occur.
Cerebral edema and cerebral infarction may be caused in women with subarachnoid hemorrhage.