Lactic acidosis is a medical condition characterized by a build-up of lactate (especially L-lactate) in the body, with formation of an excessively low pH in the bloodstream. It is a form of metabolic acidosis, in which excessive acid accumulates due to a problem with the bodys oxidative metabolism. Lactic acidosis is typically the result of an underlying acute or chronic medical condition, medication, or poisoning. The symptoms are generally attributable to these underlying causes, but may include nausea, vomiting, Kussmaul breathing (laboured and deep), and generalised weakness. The diagnosis is made on biochemical analysis of blood (often initially on arterial blood gas samples), and once confirmed, generally prompts an investigation to establish the underlying cause to treat the acidosis. In some situations, hemofiltration (purification of the blood) is temporarily required. In rare chronic forms of lactic acidosis caused by mitochondrial disease, a specific diet or dichloroacetate may be used. The prognosis of lactic acidosis depends largely on the underlying cause; in some situations (such as severe infections), it indicates an increased risk of death. Classification
The Cohen–Woods classification categorizes causes of lactic acidosis as:
Type A: Decreased tissue oxygenation (e.g., from decreased blood flow)
Type B
B1: Underlying diseases (sometimes causing type A)
B2: Medication or intoxication
B3: Inborn error of metabolism

Signs and symptoms
Lactic acidosis is commonly found in people who are unwell, such as those with severe heart and/or lung disease, a severe infection with sepsis, the systemic inflammatory response syndrome due to another cause, severe physical trauma, or severe depletion of body fluids.
Trigeminal autonomic cephalalgia (TAC) is the name for a type of primary headache that occurs with pain on one side of the head in the trigeminal nerve area and symptoms in autonomic systems on the same side, such as eye watering and redness or drooping eyelids. TACs include

Cluster headache
Paroxysmal hemicrania (chronic or episodic)
Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT)
Short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA)
Long-lasting autonomic symptoms with hemicrania (LASH)TACs can be differentiated by the length and frequency of recurrence of the headaches.Treatment for TACs varies depending on the exact type, but can include medication such as Indomethacin (in the case of chronic paroxysmal hemicrania) or acute and prophylactic therapy (in the case of cluster headache). == References ==