It is suggested that carbamazepine acts as a potent antigen that binds to the antigen-presenting area of HLA-B*1502 alike, triggering an everlasting activation signal on immature CD8-T cells, thus resulting in widespread cytotoxic reactions like SJS/TEN. Interactions
Carbamazepine has a potential for drug interactions. Drugs that decrease breaking down of carbamazepine or otherwise increase its levels include erythromycin, cimetidine, propoxyphene, and calcium channel blockers. Grapefruit juice raises the bioavailability of carbamazepine by inhibiting the enzyme CYP3A4 in the gut wall and in the liver. Lower levels of carbamazepine are seen when administrated with phenobarbital, phenytoin, or primidone, which can result in breakthrough seizure activity.Valproic acid and valnoctamide both inhibit microsomal epoxide hydrolase (mEH), the enzyme responsible for the breakdown of the active metabolite carbamazepine-10,11-epoxide into inactive metabolites. By inhibiting mEH, valproic acid and valnoctamide cause a build-up of the active metabolite, prolonging the effects of carbamazepine and delaying its excretion. Carbamazepine, as an inducer of cytochrome P450 enzymes, may increase clearance of many drugs, decreasing their concentration in the blood to subtherapeutic levels and reducing their desired effects. Drugs that are more rapidly metabolized with carbamazepine include warfarin, lamotrigine, phenytoin, theophylline, valproic acid, many benzodiazepines, and methadone. Carbamazepine also increases the metabolism of the hormones in birth control pills and can reduce their effectiveness, potentially leading to unexpected pregnancies. Pharmacology
Mechanism of action
Carbamazepine is a sodium channel blocker. It binds preferentially to voltage-gated sodium channels in their inactive conformation, which prevents repetitive and sustained firing of an action potential.
A vascular malformation is a blood vessel or lymph vessel abnormality. Vascular malformations are one of the classifications of vascular anomalies, the other grouping is vascular tumors. They may cause aesthetic problems as they have a growth cycle, and can continue to grow throughout life. Vascular malformations of the brain (VMBs) include those involving capillaries, and those involving the veins and arteries. Capillary malformations in the brain are known as cerebral cavernous malformations or capillary cavernous malformations (CCMs). Those involving the mix of vessels are known as cerebral arteriovenous malformations (AVMs or cAVMs). The arteriovenous type is the most common in the brain. Types
A simple division of the vascular malformations is made into low-flow and high-flow types. Low-flow malformations involve a single type of blood or lymph vessel, and are known as simple vascular malformations; high-flow malformations involve an artery. There are also malformations that are of mixed-flow involving more than one type of vessel, such as an arteriovenous malformation.Low-flow vascular malformations include capillary malformations, venous malformations, and lymphatic malformations. Capillary malformation
Capillary malformations involve the capillaries, and are the most common type. They used to refer only to port-wine stains but now include others. Capillary malformations are limited to the superficial layers of the skin but they can thicken, become nodular, and sometimes become disfiguring.