====== Myoclonic Jerking or Hyperreflexia ======

Drugs leading to hyperreflexia or muscle irritability are often those that may cause seizures:

  * [[:wikitox:2.1.11.9.2.1_tricyclic_antidepressants|TCA]]s
  * [[:wikitox:2.1.11.9.4_mood_stabilizers|Lithium]]
  * [[:wikitox:2.1.7.1.2_sulphonylureas|Hypoglycaemic drugs]]
  * [[:wikitox:2.2.7.4.5_organophosphates|Organophosphates]] (look for fasciculation)
  * [[:wikitox:2.1.11.9.2.3_serotonin_reuptake_inhibitors|Serotonin reuptake inhibitors]] can cause prominent myoclonus and tremor that may be confused with seizures, but are an uncommon cause of coma.

===== MYOCLONUS and HYPOTENSION =====

Directly proconvulsant drugs include TCAs, [[:wikitox:3.4.3.4.2_beta_blockers|propranolol]], [[:wikitox:chloroquine|]], [[:wikitox:2.1.11.9.4_mood_stabilizers|lithium]] and [[:wikitox:2.1.11.9.3_antipsychotics|neuroleptics]].

However, if there is compromise of CNS perfusion, then [[:wikitox:2.1.11.2_anticonvulsants|seizures]] may occur with any of these drugs.

===== MYOCLONUS, HYPERREFLEXIA and HALLUCINATIONS =====

Myoclonic jerking (without fitting) is suggestive of the [[:wikitox:serotonin_toxicity_detailed_article|serotonergic syndrome]].

Hyperadrenergic states (withdrawal states, [[:wikitox:3.2.1.3_toxidromes|sympathomimetic]] drugs) and the serotonergic syndrome are associated with hyperreflexia. In [[:wikitox:serotonin_toxicity_detailed_article|serotonin toxicity]], the hyperreflexia is typically confined to the lower limbs.

===== MYOCLONUS and ANTICHOLINERGICS =====

[[:wikitox:status_epilepticus_and_treatment_of_seizures|Seizures]] and hyperreflexia are more common with [[:wikitox:2.1.11.4.2_antihistamines|pheniramine]], TCAs (particularly amoxapine, dothiepin and desipramine) and orphenadrine.

[[:wikitox:2.1.11.9.2.3_serotonin_reuptake_inhibitors|Serotonin reuptake inhibitors]] can cause prominent myoclonus and tremor that may be confused with seizures. Hyperreflexia from SSRIs is often confined to the lower limbs.

===== MYOCLONUS and ACIDOSIS =====

Marked hyperreflexia or myoclonus in the absence of seizures suggests [[:wikitox:3.2.1.3_toxidromes|sympathomimetic]] drugs or [[:wikitox:serotonin_toxicity_detailed_article|serotonergic]] drugs.