NR607 Standardized Procedure Worksheet
Name: RUSSEL TENDE
1. Definition
a. Disease or condition
Lithium Toxicity
b. Pathophysiology
Excessive lithium levels otherwise known as lithium toxicity can result from increased intake or
reduced excretion of lithium (Heyda, Avula & Swoboda, 2023). Acute, chronic, or acute on
chronic overdose may occur due to intentional self-harm, accidental ingestion of large quantities
of lithium tablets, or from improper dose adjustments in patients on long-term lithium therapy
(Heyda, Avula & Swoboda, 2023). Impaired lithium excretion can occur from conditions causing
sodium or fluid depletion—such as vomiting, diarrhea, fever, renal insufficiency, excessive
exercise, water restriction, heavy sweating, low-sodium diets, or congestive heart failure—as
well as medications that reduce glomerular filtration rate, leading to chronic lithium toxicity
(Heyda, Avula & Swoboda, 2023). Long-term lithium use can induce nephrogenic diabetes
insipidus, reducing the kidneys’ ability to concentrate urine and increasing the risk of toxicity. A
vicious cycle may develop when intercurrent illness further compromises renal function,
worsening lithium clearance. For instance, volume depletion increases serum lithium levels,
which in turn further impairs renal concentrating ability, perpetuating toxicity (Heyda, Avula &
Swoboda, 2023).
c. Incidence and prevalence
Zaidi, Heald, Belgamwar, and Fryer (2023) state that Lithium toxicity is relatively common, with
serum levels ≥1.5 mmol/L and ≥2.0 mmol/L occurring in approximately 1% and 0.3% of
patients, respectively, requiring prompt treatment. According to Heyda, Avula, and Swoboda
(2023), a study looked at patients who were treated with lithium between 1997 and 2013 to see
how often lithium poisoning happened and whether it affected kidney function – out of 1,340
patients, 96 had at least one episode where their lithium level was higher than 1.5 mmol/L. A
group of 77 patients went through 91 such episodes, 34% of them needed intensive care, and
13% had to undergo dialysis. Some patients experienced temporary kidney problems, but their
kidney function returned to the same level as before the episode, and there were no deaths
recorded (Heyda, Avula & Swoboda, 2023). Kobylianskii, Austin, Gold and Wu (2021) also
0320 RB/KK
, state that there were 7,085 reported cases of toxic lithium exposure in the United States in 2019,
and 22% of these cases resulted in serious clinical outcomes, including four deaths.
2. Assessment
a. Symptoms
The central nervous system is said to be the main site affected by toxicity, with clinical
presentations ranging from no symptoms despite elevated drug levels to overt signs of toxicity
such as confusion, ataxia, or seizures (Vasquez et al, 2021). The clinical manifestations of
lithium toxicity depend on whether the exposure is acute, chronic, or acute on chronic
(Kobylianskii, Austin, Gold, & Wu, 2021). Acute symptoms include mostly gastrointestinal
symptoms such as nausea, vomiting, diarrhea, as well as mild or delayed neurologic symptoms
such as hand tremors, slurred speech, and vision changes (Kobylianskii, Austin, Gold, & Wu,
2021).
Chronic symptoms which result from prolonged exposure to elevated lithium levels over days to
weeks, can present with symptoms such as worsening tremor, hyperreflexia, rigidity, lethargy,
confusion, ataxia, myoclonic jerks, altered level of consciousness, nystagmus, seizures,
nephrogenic diabetes insipidus, chronic tubulointerstitial nephropathy, hypothyroidism,
hyperthyroidism, hyperparathyroidism, hypercalcemia, syndrome of irreversible lithium-
effectuated neurotoxicity (SILENT), electrocardiogram changes (T-wave inversions, QT
prolongation, ST segment depression, sinus node dysfunction, and bradycardia), as well as
dysrhythmias (Kobylianskii, Austin, Gold, & Wu, 2021; Reimann & Whyte, 2022).
b. Physical exam findings
Common physical exam findings consistent with lithium toxicity can vary depending on the
severity of toxicity (mild, moderate, or severe), but typically include neurological symptoms
such as coarse tremors (especially in the hands), (exaggerated deep tendon reflexes
(hyperreflexia), unsteady gait or difficulty with coordination (ataxia), involuntary eye
movements (nystagmus), slurred speech, sudden, brief muscle jerks (myoclonus), altered mental
status (ranging from mild confusion to delirium or stupor), seizures (in severe toxicity), and even
coma (in extreme cases) (Heyda, Avula & Swoboda, 2023). Gastrointestinal symptoms such as
nausea, vomiting, and diarrhea are also frequently observed. Some patients may exhibit
hypotension or hypertension, bradycardia, fever in severe cases, signs of dehydration such as dry
mucous membranes, poor skin turgor, irregular heart rhythm on auscultation or EKG, as well as
muscle rigidity or weakness (Heyda, Avula & Swoboda, 2023).
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Name: RUSSEL TENDE
1. Definition
a. Disease or condition
Lithium Toxicity
b. Pathophysiology
Excessive lithium levels otherwise known as lithium toxicity can result from increased intake or
reduced excretion of lithium (Heyda, Avula & Swoboda, 2023). Acute, chronic, or acute on
chronic overdose may occur due to intentional self-harm, accidental ingestion of large quantities
of lithium tablets, or from improper dose adjustments in patients on long-term lithium therapy
(Heyda, Avula & Swoboda, 2023). Impaired lithium excretion can occur from conditions causing
sodium or fluid depletion—such as vomiting, diarrhea, fever, renal insufficiency, excessive
exercise, water restriction, heavy sweating, low-sodium diets, or congestive heart failure—as
well as medications that reduce glomerular filtration rate, leading to chronic lithium toxicity
(Heyda, Avula & Swoboda, 2023). Long-term lithium use can induce nephrogenic diabetes
insipidus, reducing the kidneys’ ability to concentrate urine and increasing the risk of toxicity. A
vicious cycle may develop when intercurrent illness further compromises renal function,
worsening lithium clearance. For instance, volume depletion increases serum lithium levels,
which in turn further impairs renal concentrating ability, perpetuating toxicity (Heyda, Avula &
Swoboda, 2023).
c. Incidence and prevalence
Zaidi, Heald, Belgamwar, and Fryer (2023) state that Lithium toxicity is relatively common, with
serum levels ≥1.5 mmol/L and ≥2.0 mmol/L occurring in approximately 1% and 0.3% of
patients, respectively, requiring prompt treatment. According to Heyda, Avula, and Swoboda
(2023), a study looked at patients who were treated with lithium between 1997 and 2013 to see
how often lithium poisoning happened and whether it affected kidney function – out of 1,340
patients, 96 had at least one episode where their lithium level was higher than 1.5 mmol/L. A
group of 77 patients went through 91 such episodes, 34% of them needed intensive care, and
13% had to undergo dialysis. Some patients experienced temporary kidney problems, but their
kidney function returned to the same level as before the episode, and there were no deaths
recorded (Heyda, Avula & Swoboda, 2023). Kobylianskii, Austin, Gold and Wu (2021) also
0320 RB/KK
, state that there were 7,085 reported cases of toxic lithium exposure in the United States in 2019,
and 22% of these cases resulted in serious clinical outcomes, including four deaths.
2. Assessment
a. Symptoms
The central nervous system is said to be the main site affected by toxicity, with clinical
presentations ranging from no symptoms despite elevated drug levels to overt signs of toxicity
such as confusion, ataxia, or seizures (Vasquez et al, 2021). The clinical manifestations of
lithium toxicity depend on whether the exposure is acute, chronic, or acute on chronic
(Kobylianskii, Austin, Gold, & Wu, 2021). Acute symptoms include mostly gastrointestinal
symptoms such as nausea, vomiting, diarrhea, as well as mild or delayed neurologic symptoms
such as hand tremors, slurred speech, and vision changes (Kobylianskii, Austin, Gold, & Wu,
2021).
Chronic symptoms which result from prolonged exposure to elevated lithium levels over days to
weeks, can present with symptoms such as worsening tremor, hyperreflexia, rigidity, lethargy,
confusion, ataxia, myoclonic jerks, altered level of consciousness, nystagmus, seizures,
nephrogenic diabetes insipidus, chronic tubulointerstitial nephropathy, hypothyroidism,
hyperthyroidism, hyperparathyroidism, hypercalcemia, syndrome of irreversible lithium-
effectuated neurotoxicity (SILENT), electrocardiogram changes (T-wave inversions, QT
prolongation, ST segment depression, sinus node dysfunction, and bradycardia), as well as
dysrhythmias (Kobylianskii, Austin, Gold, & Wu, 2021; Reimann & Whyte, 2022).
b. Physical exam findings
Common physical exam findings consistent with lithium toxicity can vary depending on the
severity of toxicity (mild, moderate, or severe), but typically include neurological symptoms
such as coarse tremors (especially in the hands), (exaggerated deep tendon reflexes
(hyperreflexia), unsteady gait or difficulty with coordination (ataxia), involuntary eye
movements (nystagmus), slurred speech, sudden, brief muscle jerks (myoclonus), altered mental
status (ranging from mild confusion to delirium or stupor), seizures (in severe toxicity), and even
coma (in extreme cases) (Heyda, Avula & Swoboda, 2023). Gastrointestinal symptoms such as
nausea, vomiting, and diarrhea are also frequently observed. Some patients may exhibit
hypotension or hypertension, bradycardia, fever in severe cases, signs of dehydration such as dry
mucous membranes, poor skin turgor, irregular heart rhythm on auscultation or EKG, as well as
muscle rigidity or weakness (Heyda, Avula & Swoboda, 2023).
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