Neonates experiencing such a torsion typically present with painless scrotal swelling, discoloration, and a firm, painless mass in the scrotum. Such testes are usually necrotic from birth and must be removed surgically. : 315  The exact cause of or specific risk factors for extravaginal torsion in this population remain unclear. Intravaginal testicular torsion
Intravaginal testicular torsion occurs when the testicle rotates on the spermatic cord within the tunica vaginalis. This variant more commonly occurs in older children and adults. The "bell-clapper deformity," in which there is inappropriately high attachment of the tunica vaginalis over the spermatic cord and failure of the normal posterior attachment of the testicle to the inner scrotum, which allows the testicle to move freely within the tunica vaginalis and predisposes to intravaginal testicular torsion. Torsion of the testicular appendix
The testicular appendix is located in the upper pole of the testicle. It is an embryonic remnant that has no known function, but is at risk for torsion events. This type of torsion is the most common cause of acute scrotal pain in boys ages 7–14. Its appearance is similar to that of testicular torsion but the onset of pain is typically more gradual. Palpation reveals a small firm nodule on the upper portion of the testis which displays a characteristic "blue dot sign". This is the appendix of the testis which has become discolored and is noticeably blue through the skin. Unlike other torsions, however, the cremasteric reflex is still active.
Indeed, one suggested use for lofexidine is to ease withdrawal symptoms of methadone dependence. Its use is approved in the United States for up to 14 days. Other clinical uses
The possibility of using lofexidine to treat alcohol withdrawal symptoms has been investigated, and has not yet been shown to be an effective treatment. It is also used in treatment of cases with postmenopausal hot flashes. Special populations
Lofexidines safety in pregnancy or in the setting of breastfeeding are unknown. Caution is warranted if chronic kidney impairment is present. Adverse effects
Adverse effects that have occurred after taking lofexidine include the following:
Slow heart rate
Dizziness
Sleepiness
Mouth dryness
Low blood pressure
QT prolongationIn addition, people may experience a sudden jump in blood pressure after stopping lofexidine. Overdose
The LD50 of lofexidine is above 77 mg/kg in animals. Studies of high-dose, single administrations of lofexidine proved tolerable for animals, but repeat administration induced symptoms consistent with toxicity. In studies on mice, rats, and dogs, these included ataxia, somnolence, and tremors. It is expected that an overdose of lofexidine would result in symptoms akin to its pharmacological side effects in humans, such as bradycardia and hypotension. Interactions
Many drug-drug interactions with lofexidine are possible. QT prolongation
Lofexidine prolongs the QT interval, which can result in a severe interaction (torsade de pointes) when combined with other drugs that also prolong the QT interval. Patient-specific characteristics that increase the risk for a clinically significant drug-drug interaction include:
increasing age
female sex
cardiac disease
electrolyte disturbances (low blood potassium)As a result, there are many QT-prolonging drugs that may interact with lofexidine.