This may be due to a keratolytic enzyme secreted during stage 1.The patient with a single flea may present as early as stage 2 when, though the erythema is barely perceptible, a boring pain and the curious sensation of pleasant itching occur. This inflammatory reaction is the initial immunological response to the infestation. Heavily infested patients may not notice a stage 2 infection due to the other fleas’ causing irritation as well. Feces may be seen, but this is more common in the 3rd stage. Around the third day after penetration, erythema and skin tenderness are felt, accompanied by pruritus (severe itching) and a black furuncular nodule surrounded by a white halo of stretched skin caused by the expansion of the flea. Fecal coils may protrude from the center of the nodule where the fleas anus is facing upward. They should be washed off quickly as the feces may remain in the skin unless removed. During this 3a substage, pain can be severe, especially at night or, if the nodule is on the foot, while walking. Eggs will also begin to be released and a watery secretion can be observed. The radical metamorphosis during the 3rd to 6th day after penetration, or neosomy, precedes the formation of a small caldera-like rim rampart as a result of the increased thickness of the fleas chitin exoskeleton.
However, the associated symptoms of headaches, memory loss, and lack of concentration may be more frequent in head trauma than in idiopathic hypersomnia. "The possibility of secondary narcolepsy following head injury in previously asymptomatic individuals has also been reported." Secondary hypersomnias
Secondary hypersomnias are extremely numerous. Hypersomnia can be secondary to disorders such as clinical depression, multiple sclerosis, encephalitis, epilepsy, or obesity. Hypersomnia can also be a symptom of other sleep disorders, like sleep apnea. It may occur as an adverse effect of taking certain medications, of withdrawal from some medications, or of substance use. A genetic predisposition may also be a factor. In some cases it results from a physical problem, such as a tumor, head trauma, or dysfunction of the autonomic or central nervous system.Sleep apnea is the second most frequent cause of secondary hypersomnia, affecting up to 4% of middle-aged adults, mostly men. Upper airway resistance syndrome (UARS) is a clinical variant of sleep apnea that can also cause hypersomnia. Just as other sleep disorders (like narcolepsy) can coexist with sleep apnea, the same is true for UARS. There are many cases of UARS in which excessive daytime sleepiness persists after CPAP treatment, indicating an additional cause, or causes, of the hypersomnia and requiring further evaluation.Sleep movement disorders, such as restless legs syndrome (RLS) and periodic limb movement disorder (PLMD or PLMS) can also cause secondary hypersomnia. Although RLS does commonly cause excessive daytime sleepiness, PLMS does not. There is no evidence that PLMS plays "a role in the etiology of daytime sleepiness.