Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of serotonergic substances on the locomotor pattern and cutaneous reflexes were studied in 3 adult chronic spinal cats trained for 1-3 months to walk with their hindlimbs on a treadmill. The 5-hydroxytryptamine (5-HT) precursor, 5-hydroxytryptophan (5-HTP), and two 5-HT agonists, 5-methoxy-N,N-dimethyltryptamine and quipazine, were found to generally increase the step length and augment the amplitude of hindlimb extensors and flexors as well as axial muscles. Correspondingly, the excursion of the hip, the knee and the ankle joints was increased, mainly in the flexion direction. Cyproheptadine, a 5-HT antagonist, partially or completely antagonised these effects. The threshold current needed to elicit a flexion reflex by stimulating the dorsum of the paw through implanted wires, was lower after the injection of 5-HT agonists than in the immediately preceding control period. Fast paw shaking initiated by dipping the paw in water was unchanged after quipazine and was not abolished by cyproheptadine. In accordance with others, our results suggest that serotonergic drugs may increase the excitability of several types of spinal neurones, including motoneurones, and consequently influence the locomotor pattern as well as the reflex responsiveness. The changes observed with serotonergic agonists were different in many respects from those obtained with noradrenergic agonists and these differences are discussed. This may indicate specific roles for these classes of substances on locomotor function and reflex activity and also provide a basis for further clinical investigations.
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PMID:The effects of serotonergic drugs on the locomotor pattern and on cutaneous reflexes of the adult chronic spinal cat. 235 31

Serotonin syndrome is a potentially life-threatening condition caused by excessive serotonergic activity in the nervous system. It is characterized by mental status changes, autonomic instability, and neuromuscular hyperactivity. Most reported cases of serotonin syndrome are in patients using multiple serotonergic drugs or who have had considerable exposure to a single serotonin-augmenting drug. Diagnosis is made using the Hunter Serotonin Toxicity Criteria, which require the presence of one of the following classical features or groups of features: spontaneous clonus; inducible clonus with agitation or diaphoresis; ocular clonus with agitation or diaphoresis; tremor and hyperreflexia; or hypertonia, temperature above 100.4 degrees F (38 degrees C), and ocular or inducible clonus. Most cases of serotonin syndrome are mild and may be treated by withdrawal of the offending agent and supportive care. Benzodiazepines may be used to treat agitation and tremor. Cyproheptadine may be used as an antidote. Patients with moderate or severe cases of serotonin syndrome require hospitalization. Critically ill patients may require neuromuscular paralysis, sedation, and intubation. If serotonin syndrome is recognized and complications are managed appropriately, the prognosis is favorable.
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PMID:Prevention, recognition, and management of serotonin syndrome. 2043 30

Serotonin syndrome (SS) is an under diagnosed and under reported condition. Mild SS is easily overlooked by physicians. Every patient with mild SS is a potential candidate for developing life-threatening severe SS because of inadvertent overdose or the addition of the second serotonergic drug. Herein, we describe 12 patients with mild SS observed over 12 months in neurology outpatient clinic. It is a retrospective chart review of 12 consecutive patients who had hyperreflexia with tremor (defined as mild SS Hunter's criteria) and had received serotonergic agents in the past 5 weeks. Only four patients (33%) reported tremor as a presenting or main feature. The presenting features in another eight patients were: Dizziness, generalized body pain, headache, and seizure. Five patients responded to the removal of the offending agents and got a complete response in 2-7 days. There were no or minimal responses in another seven patients to the removal of the serotonergic drugs. Cyproheptadine was started in these patients, at the dose of 8 mg three times daily. Response started within 1-3 days of initiation of the drug and the complete responses were noted in 5-14 days. There were no side effects from cyproheptadine in any patient. We suggest that any patient on serotonergic drug developing new symptoms should be examined for the presence of tremor, hypertonia, hyperreflexia, and clonus to look for mild SS. In addition, every patient on any serotonergic drug should be examined for the presence of mild SS before escalating the dose or before adding a new one.
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PMID:Mild serotonin syndrome: A report of 12 cases. 2601 24