Neurotoxicity twitching

Neurotoxicity (damage to the nervous system by a toxic substance) may also be seen with the administration of the aminoglycosides. Signs and symptoms of neurotoxicity include numbness, skin tingling, circum-oral (around the mouth) paresthesia, peripheral paresthesia, tremors, muscle twitching, convulsions, muscle weakness, and neuromuscular blockade (acute muscular paralysis and apnea). 

MONITORING FOR NEUROTOXICITY. The nurse should be alert for symptoms such as numbness or tingling of the skin, circumoral paresthesia, peripheral paresthesia (numbness or tingling in the extremities), tremors, and muscle twitching or weakness. The nurse reports any... 

Serious react ions may include nephrotoxicity (as evidenced by increased thirst, decreased appetite, nausea, vomiting, increased BUN and serum creatinine levels, and decreased creatinine clearance) neurotoxicity (manifested as muscle twitching, visuai disturbances, seizures, and tingiing) and ototoxicity (as evidenced by tinnitus, dizziness, and loss of hearing). 

A 35-year-old woman, who was admitted for elective laparotomy and ileostomy formation was given patient-controlled analgesic with pethidine for postoperative analgesia (8). The device was set to deliver 20 mg of pethidine with a 5-minute lock-out period and no hourly limit. At 4 hours postoperatively she did not have pethidine-related neurotoxicity, but at 23 hours she had myoclonic jerks and facial twitching followed by a brief generalized tonic-clonic seizure and postictal sequelae. The pethidine was withdrawn and there was no further seizure activity. She had self administered a total of 2700 mg. The norpethidine concentration was 1.8 pg/ml. 

Kidney problems (nephrotoxicity) Twitching, numbness, or seizures (neurotoxicity) Hypersensitivity Loss of hearing and ringing in the ear Dizziness and loss of balance (ototoxicity) Tingling in fingers and toes (peripheral neuritis) ... 

Delayed neurotoxicity results from degeneration of the axons followed by demyelination (14,15,23). Clinical manifestation includes sensory disturbances, ataxia, weakness, muscle twitching and, in severe cases, complete flaccid paralysis ( 15). A fair number of organophosphate compounds are capable of inducing delayed neurotoxicity. Of the 250 organophosphates (not all pesticides) tested for delayed neurotoxicity in chickens, 47% (117 chemicals) showed positive responses (23). Notable examples of pesticides which possess this neurotoxicity are leptophos, EPN, merphos, dichlorvos, and... 

Isoniazid may precipitate convulsions, usually in patients with known seizure disorders. Optic neuritis also has occurred. Muscle twitching, dizziness, ataxia, paresthesias, stupor, and potentially fatal encephalopathy are other manifestations of neurotoxicity. A number of mental abnormalities may appear, including euphoria, transient memory inpairment, loss of self-control, and psychosis. 

Toxicity and interactions Neurotoxic effects are common and include peripheral neuritis, restlessness, muscle twitching, and insomnia. These effects can be alleviated (without blocking the antibacterial effect) by administration of pyridoxine. INH is hepatotoxic and may cause abnormal liver function tests, jaundice, and hepatitis. Fortunately, hepatotoxicity is rare in children. INH may inhibit the hepatic metabolism of dmgs, eg, phenytoin. Hemolysis has occurred in patients with glucose-6-phosphate dehydrogenase deficiency. A lupuslike syndrome has been reported. 

Patients who receive aminoglycosides may also experience nephrotoxicty (kidney), neurotoxicity (muscle twitching, numbness or seizures), and hypersensitivity. 

Studies in rats have determined that subcutaneous doses of both meperidine and normeperidine lower the seizure threshold. In contrast, after intracerebro-ventricular (ICV) administration, meperidine raised the threshold while normeperidine lowered it. Naloxone antagonized this anticonvulsant effect of ICV-administered meperidine and enhanced the pro-convulsant effect of normeperidine. Neurotoxic symptoms can range from muscle twitching and jerking to full tonic-clonic seizures. Symptoms are worsened with parenteral doses approaching 1 g/day, in patients with underlying seizure disorders, pre-eclampsia, and acute renal failure. 

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