Persistent onset is commonly paired with central vertigo signs and symptoms.The characteristics of an episodic onset vertigo are indicated by symptoms lasting for a smaller, more memorable amount of time, typically lasting for only seconds to minutes. Pathophysiology
The neurochemistry of vertigo includes six primary neurotransmitters that have been identified between the three-neuron arc that drives the vestibulo-ocular reflex (VOR). Glutamate maintains the resting discharge of the central vestibular neurons and may modulate synaptic transmission in all three neurons of the VOR arc. Acetylcholine appears to function as an excitatory neurotransmitter in both the peripheral and central synapses. Gamma-Aminobutyric acid (GABA) is thought to be inhibitory for the commissures of the medial vestibular nucleus, the connections among the cerebellar Purkinje cells, the lateral vestibular nucleus, and the vertical VOR. Three other neurotransmitters work centrally. Dopamine may accelerate vestibular compensation. Norepinephrine modulates the intensity of central reactions to vestibular stimulation and facilitates compensation. Histamine is present only centrally, but its role is unclear. Dopamine, histamine, serotonin, and acetylcholine are neurotransmitters thought to produce vomiting. It is known that centrally acting antihistamines modulate the symptoms of acute symptomatic vertigo. Diagnosis
Tests for vertigo often attempt to elicit nystagmus and to differentiate vertigo from other causes of dizziness such as presyncope, hyperventilation syndrome, disequilibrium, or psychiatric causes of lightheadedness.
Temozolomide (TMZ), sold under the brand name Temodar among others, is a medication used to treat brain tumors such as glioblastoma and anaplastic astrocytoma. It is taken by mouth or via intravenous infusion.The most common side effects with temozolomide are nausea, vomiting, constipation, loss of appetite, alopecia (hair loss), headache, fatigue, convulsions (seizures), rash, neutropenia or lymphopenia (low white-blood-cell counts), and thrombocytopenia (low blood platelet counts). People receiving the solution for infusion may also have injection-site reactions, such as pain, irritation, itching, warmth, swelling and redness, as well as bruising.Temozolomide is an alkylating agent used to treat serious brain cancers; most commonly as second-line treatments for astrocytoma and as the first-line treatment for glioblastoma. Olaparib in combination with temozolomide demonstrated substantial clinical activity in relapsed small cell lung cancer. Medical uses
In the United States temozolomide is indicated for the treatment of adults with newly diagnosed glioblastoma multiforme concomitantly with radiotherapy and subsequently as monotherapy treatment; or adults with refractory anaplastic astrocytoma who have experienced disease progression on a drug regimen containing nitrosourea and procarbazine.In the European Union temozolomide is indicated for adults with newly diagnosed glioblastoma multiforme concomitantly with radiotherapy and subsequently as monotherapy treatment; or children from the age of three years, adolescents and adults with malignant glioma, such as glioblastoma multiforme or anaplastic astrocytoma, showing recurrence or progression after standard therapy. Contraindications
Temozolomide is contraindicated in people with hypersensitivity to it or to the similar drug dacarbazine. The use of temozolomide is not recommended in people with severe myelosuppression.