Symptomdx.

Get Started

Hypokalemia SymptomsAPPROACH

ENDOCRINE, METABOLIC, AND ABNORMAL LABS · 19 SECTIONS

⚲

495 items

☷ Legend

⚲

Resuscitation and Universal Approaches9▾

Chest and Cardiovascular12▾

Respiratory11▾

Abdominal and Gastrointestinal24▾

Renal and Urinary7▾

Neurologic11▾

Back and Neck8▾

Women's Health, Pregnancy, and GU11▾

Infectious Disease and Fever Syndromes11▾

Allergy and Dermatology7▾

Musculoskeletal and Extremities14▾

Trauma and Wounds14▾

ENT, Eye, Dental10▾

Endocrine, Metabolic, and Abnormal Labs9▾

Hyperglycemia Hypoglycemia Hyponatremia Symptoms Hyperkalemia Symptoms Hypokalemia Symptoms Rhabdomyolysis Concern Anticoagulation Related Abnormal Coagulation Studies Acute Kidney Injury And Elevated Creatinine Referral Symptomatic Anemia Concern

Toxicology and Behavioral14▾

Pediatrics16▾

Environmental and Exposure4▾

01History/hx53

Presenting features

›Symptom pattern

›Weakness

›Fatigue

›Myalgias

›Cramps

›Paresthesias

›Constipation

›Palpitations

›Polyuria

›Paralysis episodes

OPQRST

›Onset

›Time course minutes to hours

›Time course days to weeks

›Provocation and palliation

›Recent vomiting

›Recent diarrhea

›Recent diuretic escalation

›Recent insulin

›Recent beta agonist

›Symptoms worse with exertion

›Quality

›Flaccid weakness

›Cramping pain

›Region and radiation

›Proximal muscle predominance

›Ascending weakness

02Alarm Features/alarm28

Immediate escalation triggers

›Resuscitation triggers

›Sustained ventricular tachycardia

›Ventricular fibrillation

›Hemodynamic instability

›Altered mental status

›Respiratory failure

›Progressive paralysis

Vital sign danger thresholds

›High risk vitals

›Systolic blood pressure under 90 mmHg

›Heart rate over 130

›Oxygen saturation under 92 percent on room air

›Respiratory rate over 30

High risk exam findings

›High risk findings

›New focal weakness not consistent with metabolic pattern

›Bulbar weakness

›Hyporeflexia with rapidly progressive weakness

›Signs of volume depletion

High risk historical triggers

›High risk exposures

›Digoxin exposure

›Amphotericin exposure

›Recent large insulin dose

›Recent beta agonist escalation

›Recent high dose loop diuretic

03Medications/meds23

Current medication review

›Potassium lowering agents

›Loop diuretics

›Thiazide diuretics

›Mineralocorticoid excess agents

›High dose penicillins

›Amphotericin B

›Insulin

›Beta agonists

›Drugs increasing risk of arrhythmia

›Digoxin

›QT prolonging agents

OTC and supplements

›Nonprescription exposures

›Laxatives

›Herbal diuretics

›Licorice

Adherence and recent changes

›Medication pattern

›Missed potassium supplements

›Recent dose increase diuretic

›Recent vomiting induced poor absorption

Contraindications and interaction traps

›High risk combinations

›Potassium repletion with significant renal failure

›Potassium repletion with oliguria

›IV potassium with dextrose containing fluids

04Diet/diet17

Intake pattern

›Dietary factors

›Poor oral intake

›Very low potassium diet

›Eating disorder behaviors

Hydration pattern

›Volume status clues

›Reduced intake

›Excess free water intake

›High output losses

Caffeine and stimulants

›Stimulant exposure

›Energy drinks

›High caffeine intake

Alcohol exposure

›Alcohol related risks

›Binge drinking

›Alcohol withdrawal physiology

Trigger foods and patterns

›Episodic trigger pattern

›High carbohydrate meals preceding weakness

›High sodium intake with diuretic use

05Review of Systems/ros29

Cardiopulmonary

›Cardiopulmonary symptoms

›Palpitations

›Chest pain

›Dyspnea

›Orthopnea

›Syncope

Neuromuscular

›Neurologic symptoms

›Weakness

›Paralysis

›Paresthesias

›Muscle cramps

›Tremor

Gastrointestinal

›GI symptoms

›Vomiting

›Diarrhea

›Abdominal pain

›Constipation

Renal and endocrine

›Renal endocrine symptoms

›Polyuria

›Polydipsia

›Weight change

›Heat intolerance

Infection and inflammatory

›Systemic symptoms

06Collateral History and Family History/chafh14

Collateral source

›Collateral and reliability

›Family report

›Caregiver report

›Pharmacy fill history

Family history

›Inherited and familial conditions

›Familial periodic paralysis

›Thyroid disease

›Early sudden cardiac death

Household and exposure

›Environmental context

›Shared gastroenteritis in household

›Sick contacts

Social support reliability

›Discharge support

›Ability to obtain repeat labs

›Medication access reliability

07Risk Factors/rf24

Comorbid risks

›Medical risk factors

›Heart failure (I50.9)

›Coronary artery disease (I25.10)

›Chronic kidney disease (N18.9)

›Cirrhosis (K74.60)

›Diabetes mellitus (E11.9)

Loss and shift risks

›Potassium loss risks

›Vomiting

›Diarrhea

›High ostomy output

›Diuretic therapy

›Transcellular shift risks

›Alkalosis

›Insulin therapy

›Beta agonist therapy

Procedure and device risks

›Iatrogenic factors

›Recent dialysis

›Recent insulin infusion

Special populations

›Higher risk populations

›Pregnancy

›Pediatrics

›Elderly

›Malnutrition

›Alcohol use disorder

08Differential Diagnosis/ddx51

Life threatening

›Life threatening causes and complications

›Ventricular arrhythmia due to hypokalemia (I49.9)

›Risk increased with digoxin

›Risk increased with hypomagnesemia

›Respiratory muscle weakness with hypoventilation (J96.00)

›Bulbar symptoms increase risk

›Rapid progression increases risk

›Rhabdomyolysis (M62.82)

›Myalgias

›Dark urine

Common

›Common etiologies

›Diuretic associated renal potassium loss

›Loop diuretics

›Thiazide diuretics

›Gastrointestinal potassium loss

›Vomiting

›Diarrhea

›Poor intake with concurrent losses

›Malnutrition

›Refeeding physiology

›Hypomagnesemia associated renal potassium wasting (E83.42)

›Alcohol use disorder

›Proton pump inhibitor exposure

Less common

›Less common etiologies

›Primary hyperaldosteronism (E26.01)

09Past Medical History/pmh20

Relevant chronic conditions

›Chronic conditions

›Chronic diarrhea syndromes

›Eating disorders (F50.9)

›Heart failure (I50.9)

›Chronic kidney disease (N18.9)

›Hypertension (I10)

Prior episodes and outcomes

›Prior hypokalemia history

›Prior nadir potassium value

›Prior need for IV replacement

›Prior arrhythmia history

Surgeries and procedures

›GI and renal procedures

›Bariatric surgery

›Ileostomy or colostomy

›Nephrectomy

Devices and monitoring

›Implanted and supportive devices

›Pacemaker

›ICD

Baseline function

›Baseline status

›Baseline exercise tolerance

›Baseline neurologic deficits

10Physical Exam/exam36

General and vitals

›General appearance

›Toxic appearance

›Dehydration signs

›Altered mental status

›Vital sign interpretation

›Tachycardia pattern

›Hypotension pattern

Cardiovascular

›Cardiac exam

›Irregular rhythm

›Signs of heart failure

›Peripheral edema

Respiratory

›Respiratory exam

›Work of breathing

›Shallow respirations

›Signs of aspiration

Neurologic and neuromuscular

›Neuromuscular exam

›Proximal strength testing

›Distal strength testing

›Reflexes

›Sensation

›Gait

›Cranial nerve screen

›Bulbar and respiratory muscle screen

›Single breath count

11Lab Studies/labs33

Core electrolytes and renal function

›Basic metabolic panel

›Potassium severity classification

›Mild 3.0 to 3.4 mmol/L

›Moderate 2.5 to 2.9 mmol/L

›Severe under 2.5 mmol/L

›Sodium

›Chloride

›Bicarbonate

›Creatinine

›Glucose

Magnesium and phosphate

›Associated electrolyte abnormalities

›Magnesium

›Phosphate

›Calcium

Acid base evaluation

›Acid base assessment

›Venous blood gas if severe symptoms

›Serum bicarbonate pattern

Urine studies for etiology

›Urine electrolytes

›Urine potassium

›Urine chloride

›Urine creatinine

›Renal potassium wasting indicators

›Spot urine potassium over 20 mmol/L suggests renal loss

›Low urine potassium suggests extrarenal loss

12Imaging/img12

Scoring Systems

›Not routinely indicated scoring tools

›No validated ED scoring system specific to hypokalemia etiology

›Risk stratification based on potassium value and ECG findings

MRI

›MRI considerations

›Not routine for isolated hypokalemia

›MRI brain if focal neurologic deficit not explained metabolically

›CT considerations

›CT head if acute focal deficit or altered mental status unexplained

›CT abdomen pelvis if severe abdominal pain with suspected obstruction

Ultrasound

›Ultrasound considerations

›POCUS volume status assessment

›POCUS bladder volume if urinary retention concern

13Special Tests/spec12

Bedside respiratory assessment

›Respiratory muscle screening

›Negative inspiratory force if progressive weakness

›Forced vital capacity if bulbar symptoms

Toxicology and exposure evaluation

›Exposure confirmation

›Medication reconciliation with pharmacy

›Laxative screen when history unreliable

Renal and endocrine workup extensions

›Specialized interpretation tools

›Transtubular potassium gradient interpretation local protocol dependent

›Urine chloride helps separate vomiting from diuretic effect

Functional testing

›Neurologic escalation tests

›Neurology consult if atypical pattern

›Lumbar puncture only if alternative diagnosis suspected

14ECG/ecg19

Indications and timing

›ECG use

›Any potassium under 3.0 mmol/L with symptoms

›Any severe hypokalemia under 2.5 mmol/L

›Palpitations

›Syncope

›Digoxin exposure

Typical hypokalemia patterns

›ECG patterns

›ST depression

›T wave flattening

›Prominent U waves

›Apparent QT prolongation due to QU prolongation

High risk ECG findings

›High risk patterns

›Ventricular ectopy

›Polymorphic ventricular tachycardia

›Atrial tachyarrhythmias

Serial ECG logic

›Repeat ECG triggers

›New symptoms during repletion

›Potassium remains under 3.0 mmol/L with ongoing symptoms

›After significant IV replacement in high risk patients

15Assessment/ax21

Working diagnosis and severity

›Hypokalemia (E87.6)

›Symptomatic status

›Severity by potassium value

›ECG involvement

Etiology framework

›Mechanism classification

›Extrarenal losses

›Renal losses

›Transcellular shift

›Reduced intake

Complications to rule out

›Complication screen

›Arrhythmia

›Respiratory compromise

›Rhabdomyolysis

›Concurrent hypomagnesemia

Key supporting evidence

›Evidence summary

›History of losses or diuretics

›Urine potassium pattern supports mechanism

›Acid base pattern supports mechanism

Diagnostic uncertainty and alternatives

›Alternative diagnoses

›Neurologic emergency if focal deficits

›Toxicologic causes if history inconsistent

16Plan/plan51

Differential Management

›!Hypokalemia→›!Diabetic Ketoacidosis (DKA)→

First 5 minutes

›Critical patient workflow

›Cardiac monitor

›IV access

›ECG if severe symptoms or potassium under 3.0 mmol/L

›Point of care glucose if altered mental status

›Escalate to resuscitation bay if unstable rhythm

Potassium replacement strategy

›Replacement decision points

›Oral preferred if mild to moderate and able to tolerate

›IV preferred if severe under 2.5 mmol/L

›IV preferred if ECG changes

›IV preferred if paralysis

›Oral potassium chloride examples

›Potassium chloride 40 mmol once

›Potassium chloride 20 mmol every 2 to 4 hours

›Typical daily total 60 to 120 mmol divided doses

›IV potassium chloride examples

›Peripheral infusion 10 mmol per hour

›Central infusion 20 mmol per hour with continuous ECG monitoring

›Concentration and rate per local protocol dependent

›Repletion safety

›Avoid dextrose containing fluids during active repletion when shift suspected

›Use infusion pump

›Frequent site checks for peripheral infusions

17Disposition/dispo24

ICU criteria

›ICU level care indicators

›Severe hypokalemia under 2.5 mmol/L with symptoms

›Ventricular arrhythmia

›Significant ECG changes with ongoing replacement

›Respiratory muscle weakness

Inpatient admission criteria

›Admission indicators

›Ongoing potassium losses not controlled

›Need for repeated IV replacement

›Refractory hypokalemia with hypomagnesemia

›High risk comorbidity heart failure or coronary disease

Observation pathway criteria

›Observation suitable

›Moderate hypokalemia 2.5 to 2.9 mmol/L with mild symptoms

›Single round IV replacement with stable ECG

›Reliable follow up and repeat labs within 24 hours

Discharge criteria

›Discharge requirements

›Symptoms resolved or clearly improving

›Potassium at least 3.0 mmol/L and rising

›No concerning ECG changes

›Etiology addressed or plan in place

›Reliable follow up arranged

Follow up timing

›Follow up plan

›Repeat potassium within 24 to 72 hours based on severity

›Primary care follow up within 1 week

18Discharge Instructions/di21

Copy discharge instructions

›Diagnosis summary

›Low potassium level caused symptoms

›Potassium was treated and is improving

›Medications

›Take potassium supplement exactly as prescribed

›Do not take extra doses unless instructed

›If on diuretics follow the updated dose plan

›Diet and fluids

›Maintain normal hydration

›Include potassium containing foods unless told not to

›Follow up

›Get repeat bloodwork within the recommended timeframe

›Follow up with your clinician within 1 week

›Return to emergency criteria

›Chest pain

›Fainting

›Severe weakness

›Trouble breathing

›New palpitations

›Persistent vomiting

›New neurologic symptoms

19References/r7

Guidelines and key sources

›Reference list

›American Heart Association Guidelines for CPR and ECC 2020

›American Heart Association Focused Updates to CPR and ECC 2023

›Endocrine Society Clinical Practice Guideline Primary Aldosteronism 2016

›KDIGO Clinical Practice Guideline for Acute Kidney Injury 2012

›Gennari FJ Hypokalemia New England Journal of Medicine 1998

›Local hospital electrolyte replacement protocol local protocol dependent

Evidence & Review

Reviewed by SymptomDx Medical Team · Last reviewed February 24, 2026

SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.

Hypokalemia SymptomsAPPROACH

ENDOCRINE, METABOLIC, AND ABNORMAL LABS · 19 SECTIONS

⚲

495 items

☷ Legend

⚲

Resuscitation and Universal Approaches9▾

Chest and Cardiovascular12▾

Respiratory11▾

Abdominal and Gastrointestinal24▾

Renal and Urinary7▾

Neurologic11▾

Back and Neck8▾

Women's Health, Pregnancy, and GU11▾

Infectious Disease and Fever Syndromes11▾

Allergy and Dermatology7▾

Musculoskeletal and Extremities14▾

Trauma and Wounds14▾

ENT, Eye, Dental10▾

Endocrine, Metabolic, and Abnormal Labs9▾

Toxicology and Behavioral14▾

Pediatrics16▾

Environmental and Exposure4▾

01History/hx53

Presenting features

›Symptom pattern

›Weakness

›Fatigue

›Myalgias

›Cramps

›Paresthesias

›Constipation

›Palpitations

›Polyuria

›Paralysis episodes

OPQRST

›Onset

›Time course minutes to hours

›Time course days to weeks

›Provocation and palliation

›Recent vomiting

›Recent diarrhea

›Recent diuretic escalation

›Recent insulin

›Recent beta agonist

›Symptoms worse with exertion

›Quality

›Flaccid weakness

›Cramping pain

›Region and radiation

›Proximal muscle predominance

›Ascending weakness

02Alarm Features/alarm28

Immediate escalation triggers

›Resuscitation triggers

›Sustained ventricular tachycardia

›Ventricular fibrillation

›Hemodynamic instability

›Altered mental status

›Respiratory failure

›Progressive paralysis

Vital sign danger thresholds

›High risk vitals

›Systolic blood pressure under 90 mmHg

›Heart rate over 130

›Oxygen saturation under 92 percent on room air

›Respiratory rate over 30

High risk exam findings

›High risk findings

›New focal weakness not consistent with metabolic pattern

›Bulbar weakness

›Hyporeflexia with rapidly progressive weakness

›Signs of volume depletion

High risk historical triggers

›High risk exposures

›Digoxin exposure

›Amphotericin exposure

›Recent large insulin dose

›Recent beta agonist escalation

›Recent high dose loop diuretic

03Medications/meds23

Current medication review

›Potassium lowering agents

›Loop diuretics

›Thiazide diuretics

›Mineralocorticoid excess agents

›High dose penicillins

›Amphotericin B

›Insulin

›Beta agonists

›Drugs increasing risk of arrhythmia

›Digoxin

›QT prolonging agents

OTC and supplements

›Nonprescription exposures

›Laxatives

›Herbal diuretics

›Licorice

Adherence and recent changes

›Medication pattern

›Missed potassium supplements

›Recent dose increase diuretic

›Recent vomiting induced poor absorption

Contraindications and interaction traps

›High risk combinations

›Potassium repletion with significant renal failure

›Potassium repletion with oliguria

›IV potassium with dextrose containing fluids

04Diet/diet17

Intake pattern

›Dietary factors

›Poor oral intake

›Very low potassium diet

›Eating disorder behaviors

Hydration pattern

›Volume status clues

›Reduced intake

›Excess free water intake

›High output losses

Caffeine and stimulants

›Stimulant exposure

›Energy drinks

›High caffeine intake

Alcohol exposure

›Alcohol related risks

›Binge drinking

›Alcohol withdrawal physiology

Trigger foods and patterns

›Episodic trigger pattern

›High carbohydrate meals preceding weakness

›High sodium intake with diuretic use

05Review of Systems/ros29

Cardiopulmonary

›Cardiopulmonary symptoms

›Palpitations

›Chest pain

›Dyspnea

›Orthopnea

›Syncope

Neuromuscular

›Neurologic symptoms

›Weakness

›Paralysis

›Paresthesias

›Muscle cramps

›Tremor

Gastrointestinal

›GI symptoms

›Vomiting

›Diarrhea

›Abdominal pain

›Constipation

Renal and endocrine

›Renal endocrine symptoms

›Polyuria

›Polydipsia

›Weight change

›Heat intolerance

Infection and inflammatory

›Systemic symptoms

06Collateral History and Family History/chafh14

Collateral source

›Collateral and reliability

›Family report

›Caregiver report

›Pharmacy fill history

Family history

›Inherited and familial conditions

›Familial periodic paralysis

›Thyroid disease

›Early sudden cardiac death

Household and exposure

›Environmental context

›Shared gastroenteritis in household

›Sick contacts

Social support reliability

›Discharge support

›Ability to obtain repeat labs

›Medication access reliability

07Risk Factors/rf24

Comorbid risks

›Medical risk factors

›Heart failure (I50.9)

›Coronary artery disease (I25.10)

›Chronic kidney disease (N18.9)

›Cirrhosis (K74.60)

›Diabetes mellitus (E11.9)

Loss and shift risks

›Potassium loss risks

›Vomiting

›Diarrhea

›High ostomy output

›Diuretic therapy

›Transcellular shift risks

›Alkalosis

›Insulin therapy

›Beta agonist therapy

Procedure and device risks

›Iatrogenic factors

›Recent dialysis

›Recent insulin infusion

Special populations

›Higher risk populations

›Pregnancy

›Pediatrics

›Elderly

›Malnutrition

›Alcohol use disorder

08Differential Diagnosis/ddx51

Life threatening

›Life threatening causes and complications

›Ventricular arrhythmia due to hypokalemia (I49.9)

›Risk increased with digoxin

›Risk increased with hypomagnesemia

›Respiratory muscle weakness with hypoventilation (J96.00)

›Bulbar symptoms increase risk

›Rapid progression increases risk

›Rhabdomyolysis (M62.82)

›Myalgias

›Dark urine

Common

›Common etiologies

›Diuretic associated renal potassium loss

›Loop diuretics

›Thiazide diuretics

›Gastrointestinal potassium loss

›Vomiting

›Diarrhea

›Poor intake with concurrent losses

›Malnutrition

›Refeeding physiology

›Hypomagnesemia associated renal potassium wasting (E83.42)

›Alcohol use disorder

›Proton pump inhibitor exposure

Less common

›Less common etiologies

›Primary hyperaldosteronism (E26.01)

09Past Medical History/pmh20

Relevant chronic conditions

›Chronic conditions

›Chronic diarrhea syndromes

›Eating disorders (F50.9)

›Heart failure (I50.9)

›Chronic kidney disease (N18.9)

›Hypertension (I10)

Prior episodes and outcomes

›Prior hypokalemia history

›Prior nadir potassium value

›Prior need for IV replacement

›Prior arrhythmia history

Surgeries and procedures

›GI and renal procedures

›Bariatric surgery

›Ileostomy or colostomy

›Nephrectomy

Devices and monitoring

›Implanted and supportive devices

›Pacemaker

›ICD

Baseline function

›Baseline status

›Baseline exercise tolerance

›Baseline neurologic deficits

10Physical Exam/exam36

General and vitals

›General appearance

›Toxic appearance

›Dehydration signs

›Altered mental status

›Vital sign interpretation

›Tachycardia pattern

›Hypotension pattern

Cardiovascular

›Cardiac exam

›Irregular rhythm

›Signs of heart failure

›Peripheral edema

Respiratory

›Respiratory exam

›Work of breathing

›Shallow respirations

›Signs of aspiration

Neurologic and neuromuscular

›Neuromuscular exam

›Proximal strength testing

›Distal strength testing

›Reflexes

›Sensation

›Gait

›Cranial nerve screen

›Bulbar and respiratory muscle screen

›Single breath count

11Lab Studies/labs33

Core electrolytes and renal function

›Basic metabolic panel

›Potassium severity classification

›Mild 3.0 to 3.4 mmol/L

›Moderate 2.5 to 2.9 mmol/L

›Severe under 2.5 mmol/L

›Sodium

›Chloride

›Bicarbonate

›Creatinine

›Glucose

Magnesium and phosphate

›Associated electrolyte abnormalities

›Magnesium

›Phosphate

›Calcium

Acid base evaluation

›Acid base assessment

›Venous blood gas if severe symptoms

›Serum bicarbonate pattern

Urine studies for etiology

›Urine electrolytes

›Urine potassium

›Urine chloride

›Urine creatinine

›Renal potassium wasting indicators

›Spot urine potassium over 20 mmol/L suggests renal loss

›Low urine potassium suggests extrarenal loss

12Imaging/img12

Scoring Systems

›Not routinely indicated scoring tools

›No validated ED scoring system specific to hypokalemia etiology

›Risk stratification based on potassium value and ECG findings

MRI

›MRI considerations

›Not routine for isolated hypokalemia

›MRI brain if focal neurologic deficit not explained metabolically

›CT considerations

›CT head if acute focal deficit or altered mental status unexplained

›CT abdomen pelvis if severe abdominal pain with suspected obstruction

Ultrasound

›Ultrasound considerations

›POCUS volume status assessment

›POCUS bladder volume if urinary retention concern

13Special Tests/spec12

Bedside respiratory assessment

›Respiratory muscle screening

›Negative inspiratory force if progressive weakness

›Forced vital capacity if bulbar symptoms

Toxicology and exposure evaluation

›Exposure confirmation

›Medication reconciliation with pharmacy

›Laxative screen when history unreliable

Renal and endocrine workup extensions

›Specialized interpretation tools

›Transtubular potassium gradient interpretation local protocol dependent

›Urine chloride helps separate vomiting from diuretic effect

Functional testing

›Neurologic escalation tests

›Neurology consult if atypical pattern

›Lumbar puncture only if alternative diagnosis suspected

14ECG/ecg19

Indications and timing

›ECG use

›Any potassium under 3.0 mmol/L with symptoms

›Any severe hypokalemia under 2.5 mmol/L

›Palpitations

›Syncope

›Digoxin exposure

Typical hypokalemia patterns

›ECG patterns

›ST depression

›T wave flattening

›Prominent U waves

›Apparent QT prolongation due to QU prolongation

High risk ECG findings

›High risk patterns

›Ventricular ectopy

›Polymorphic ventricular tachycardia

›Atrial tachyarrhythmias

Serial ECG logic

›Repeat ECG triggers

›New symptoms during repletion

›Potassium remains under 3.0 mmol/L with ongoing symptoms

›After significant IV replacement in high risk patients

15Assessment/ax21

Working diagnosis and severity

›Hypokalemia (E87.6)

›Symptomatic status

›Severity by potassium value

›ECG involvement

Etiology framework

›Mechanism classification

›Extrarenal losses

›Renal losses

›Transcellular shift

›Reduced intake

Complications to rule out

›Complication screen

›Arrhythmia

›Respiratory compromise

›Rhabdomyolysis

›Concurrent hypomagnesemia

Key supporting evidence

›Evidence summary

›History of losses or diuretics

›Urine potassium pattern supports mechanism

›Acid base pattern supports mechanism

Diagnostic uncertainty and alternatives

›Alternative diagnoses

›Neurologic emergency if focal deficits

›Toxicologic causes if history inconsistent

16Plan/plan51

Differential Management

›!Hypokalemia→›!Diabetic Ketoacidosis (DKA)→

First 5 minutes

›Critical patient workflow

›Cardiac monitor

›IV access

›ECG if severe symptoms or potassium under 3.0 mmol/L

›Point of care glucose if altered mental status

›Escalate to resuscitation bay if unstable rhythm

Potassium replacement strategy

›Replacement decision points

›Oral preferred if mild to moderate and able to tolerate

›IV preferred if severe under 2.5 mmol/L

›IV preferred if ECG changes

›IV preferred if paralysis

›Oral potassium chloride examples

›Potassium chloride 40 mmol once

›Potassium chloride 20 mmol every 2 to 4 hours

›Typical daily total 60 to 120 mmol divided doses

›IV potassium chloride examples

›Peripheral infusion 10 mmol per hour

›Central infusion 20 mmol per hour with continuous ECG monitoring

›Concentration and rate per local protocol dependent

›Repletion safety

›Avoid dextrose containing fluids during active repletion when shift suspected

›Use infusion pump

›Frequent site checks for peripheral infusions

17Disposition/dispo24

ICU criteria

›ICU level care indicators

›Severe hypokalemia under 2.5 mmol/L with symptoms

›Ventricular arrhythmia

›Significant ECG changes with ongoing replacement

›Respiratory muscle weakness

Inpatient admission criteria

›Admission indicators

›Ongoing potassium losses not controlled

›Need for repeated IV replacement

›Refractory hypokalemia with hypomagnesemia

›High risk comorbidity heart failure or coronary disease

Observation pathway criteria

›Observation suitable

›Moderate hypokalemia 2.5 to 2.9 mmol/L with mild symptoms

›Single round IV replacement with stable ECG

›Reliable follow up and repeat labs within 24 hours

Discharge criteria

›Discharge requirements

›Symptoms resolved or clearly improving

›Potassium at least 3.0 mmol/L and rising

›No concerning ECG changes

›Etiology addressed or plan in place

›Reliable follow up arranged

Follow up timing

›Follow up plan

›Repeat potassium within 24 to 72 hours based on severity

›Primary care follow up within 1 week

18Discharge Instructions/di21

Copy discharge instructions

›Diagnosis summary

›Low potassium level caused symptoms

›Potassium was treated and is improving

›Medications

›Take potassium supplement exactly as prescribed

›Do not take extra doses unless instructed

›If on diuretics follow the updated dose plan

›Diet and fluids

›Maintain normal hydration

›Include potassium containing foods unless told not to

›Follow up

›Get repeat bloodwork within the recommended timeframe

›Follow up with your clinician within 1 week

›Return to emergency criteria

›Chest pain

›Fainting

›Severe weakness

›Trouble breathing

›New palpitations

›Persistent vomiting

›New neurologic symptoms

19References/r7

Guidelines and key sources

›Reference list

›American Heart Association Guidelines for CPR and ECC 2020

›American Heart Association Focused Updates to CPR and ECC 2023

›Endocrine Society Clinical Practice Guideline Primary Aldosteronism 2016

›KDIGO Clinical Practice Guideline for Acute Kidney Injury 2012

›Gennari FJ Hypokalemia New England Journal of Medicine 1998

›Local hospital electrolyte replacement protocol local protocol dependent

Evidence & Review

Reviewed by SymptomDx Medical Team · Last reviewed February 24, 2026

SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.