Serotonin syndrome has occurred in patients receiving concurrent antidepressant therapy with selective serotonin reuptake inhibitors (SSRIs) or monoamine oxidase inhibitors, or other medication types (see Interactions below). Convulsive seizures sometimes observed in patients receiving parenteral pethidine on a chronic basis have been attributed to accumulation in plasma of the metabolite norpethidine (normeperidine). Fatalities have occurred following either oral or intravenous pethidine overdose. Interactions
Pethidine has serious interactions that can be dangerous with monoamine oxidase inhibitors (e.g., furazolidone, isocarboxazid, moclobemide, phenelzine, procarbazine, selegiline, tranylcypromine). Such patients may suffer agitation, delirium, headache, convulsions, and/or hyperthermia. Fatal interactions have been reported including the death of Libby Zion. Seizures may develop when tramadol is given intravenously following, or with, pethidine. It can interact as well with SSRIs and other antidepressants, antiparkinson agents, migraine therapy, stimulants and other agents causing serotonin syndrome. It is thought to be caused by an increase in cerebral serotonin concentrations. It is probable that pethidine can also interact with a number of other medications, including muscle relaxants, benzodiazepines, and ethanol. Mechanism of action
Like morphine, pethidine exerts its analgesic effects by acting as an agonist at the μ-opioid receptor.Pethidine is often employed in the treatment of postanesthetic shivering. The pharmacologic mechanism of this antishivering effect is not fully understood, but it may involve the stimulation of κ-opioid receptors.Pethidine has structural similarities to atropine and other tropane alkaloids and may have some of their effects and side effects. In addition to these opioidergic and anticholinergic effects, it has local anesthetic activity related to its interactions with sodium ion channels.
Labial fusion is a medical condition of the female genital anatomy where the labia minora become fused together. It is generally a pediatric condition. Presentation
Labial fusion is rarely present at birth, but rather acquired later in infancy, since it is caused by insufficient estrogen exposure and newborns have been exposed to maternal estrogen in utero. It typically presents in infants at least 3 months old. Most presentations are asymptomatic and are discovered by a parent or during routine medical examination. In other cases, patients may present with associated symptoms of dysuria, urinary frequency, refusal to urinate, or post-void dribbling. Some patients present with vaginal discharge due to pooling of urine in the vulval vestibule or vagina. Complications
Labial fusion can lead to urinary tract infection, vulvar vestibulitis and inflammation caused by chronic urine exposure. In severe cases, labial adhesions can cause complete obstruction of the urethra, leading to anuria and urinary retention. Pathophysiology
The primary contributing factor to labial fusion is low estrogen levels. A vulva with low estrogen exposure, such as that of a preadolescent, has delicate epithelial lining and is therefore vulnerable to irritation. Conditions causing irritation, such as infection, inflammation and trauma, cause the edges of the labia minora to fuse together. The fusion typically begins at the posterior frenulum of the labia minora and continues anteriorly.Most labial adhesions resolve spontaneously before puberty as estrogen levels increase and the vaginal epithelium becomes cornified. Diagnosis
The condition can be diagnosed based on inspection of the vulva.