CITALOPRAM   Also explore   Side-Effects

• 0.0 OVERVIEW
• 0.1 LIFE SUPPORT
• A. This overview assumes that basic life support measures have been instituted.
• 0.2 CLINICAL EFFECTS
• 0.2.1 SUMMARY OF EXPOSURE
• A. OVERDOSE EFFECTS -
• 1. Several reports of overdose with citalopram have resulted in death following doses greater than 2000 mg. Toxic effects have included seizures, serotonin syndrome, cardiovascular effects of prolonged QTc interval.
• B. ADVERSE EFFECTS -
• 1. Nausea, vomiting, and xerostomia were frequent adverse effects reported during therapeutic use.
• 2. CNS adverse effects have included headache, insomnia, tremor, dizziness, restlessness, and sedation.
• 0.2.5 CARDIOVASCULAR
• A. ECG abnormalities, including QTc prolongation, have occurred following severe citalopram overdose.
• 0.2.7 NEUROLOGIC
• A. Seizures have occurred following overdose with citalopram and appear to be dose-dependent. Rarely, fatal serotonin syndrome has occurred following intentional overdose of citalopram and moclobemide.
• 0.2.8 GASTROINTESTINAL
• A. Nausea and vomiting have been commonly reported with citalopram therapy.
• 0.2.9 HEPATIC
• A. Abnormal hepatic function tests have occurred during therapeutic use.
• 0.4 TREATMENT OVERVIEW
• 0.4.2 ORAL/PARENTERAL EXPOSURE
• A. EMESIS: Ipecac-induced emesis is not recommended because of the potential for CNS depression and seizures.
• B. GASTRIC LAVAGE: Consider after ingestion of a potentially life-threatening amount of poison if it can be performed soon after ingestion (generally within 1 hour). Protect airway by placement in Trendelenburg and left lateral decubitus position or by endotracheal intubation. Control any seizures first.
• 1. CONTRAINDICATIONS: Loss of airway protective reflexes or decreased level of consciousness in unintubated patients; following ingestion of corrosives; hydrocarbons (high aspiration potential); patients at risk of hemorrhage or gastrointestinal perforation; and trivial or non-toxic ingestion.
• C. ACTIVATED CHARCOAL: Administer charcoal as slurry (240 mL water/30 g charcoal). Usual dose: 25 to 100 g in adults/adolescents, 25 to 50 g in children (1 to 12 years), and 1 g/kg in infants less than 1 year old.
• D. SEIZURES: Administer a benzodiazepine IV; DIAZEPAM (ADULT: 5 to 10 mg, repeat every 10 to 15 min as needed. CHILD: 0.2 to 0.5 mg/kg, repeat every 5 min as needed) or LORAZEPAM (ADULT: 4 to 8 mg; CHILD: 0.05 to 0.1 mg/kg).
• 1. Consider phenobarbital if seizures recur after diazepam 30 mg (adults) or 10 mg (children > 5 years).
• 2. Monitor for hypotension, dysrhythmias, respiratory depression, and need for endotracheal intubation. Evaluate for hypoglycemia, electrolyte disturbances, hypoxia.
• E. TORSADE DE POINTES: Hemodynamically unstable patients require electrical cardioversion. Treat stable patients with magnesium, isoproterenol, and/or atrial overdrive pacing. Correct electrolyte abnormalities (hypomagnesemia, hypokalemia, hypocalcemia).
• 1. MAGNESIUM SULFATE/DOSE: ADULTS: 2 g IV over 1 to 2 min, repeat 2 g bolus and begin infusion of 3 to 20 mg/min if dysrhythmias recur. CHILDREN: 25 to 50 mg/kg diluted to 10 mg/mL; infuse IV over 5 to 15 min.
• 2. ISOPROTERENOL/DOSE: Correct hypovolemia first. ADULT: 2 to 10 mcg/minute (CHILD: 0.1 to 1 mcg/kg/minute) IV infusion; titrate to heart rate and rhythm response. Mix 1 mg isoproterenol HCl in 500 mL D5W for a 2 mcg/mL solution.
• 3. OVERDRIVE PACING: Begin at 130 to 150 beats per min, decrease as tolerated.
• 4. Avoid class Ia (quinidine, disopyramide, procainamide, aprindine) and most class III antiarrhythmics (N-acetylprocainamide, sotalol).
• 0.5 RANGE OF TOXICITY
• A. Ingestion of less than 600 milligrams in adults generally results in mild effects. Seizures have developed following overdoses which have exceeded 600 mg of citalopram. Five non-fatal cases of citalopram overdose (up to 5200 mg) resulted in seizures developing in 4 cases and all (five cases) had QT prolongation, sinus tachycardia and inferolateral repolarization disturbances.
• B. LACK OF EFFECT - Doses as high as 2000 mg have been taken without observable cardiovascular abnormalities.
• 1.0 SUBSTANCES INCLUDED/SYNONYMS
• 1.1 THERAPEUTIC/TOXIC CLASS
• A. Citalopram hydrobromide is a phthalane derivative like other second generation antidepressant agents. However, it is currently the most highly selective and potent serotonin reuptake inhibitor. Citalopram enhances serotoninergic neurotransmission through selective and potent inhibition of neuronal serotonin reuptake. Anticholinergic effects may occur with this agent.
• 1.2 SPECIFIC SUBSTANCES

o             LU-10-171

o             Nitalapram hydrobromide

o             1-(3-dimethylaminopropyl)-1-(p-fluorophenyl)-5-

o              -phthalan carbonitrile

o             CAS 59729-33-8 (citalopram)

o             CAS 59729-32-7 (citalopram hydrobromide)

o             Molecular Formula:  C20-H21-F-N2-O, HBr

• 1.6 AVAILABLE FORMS/SOURCES
• A. FORM
• 1. Commercially available in 20 mg and 40 mg tablets, and 10 mg/5 mL oral solution
• B. USES
• 1. Citalopram is used in the treatment of depression, panic disorder, alcohol withdrawal, various pain syndromes including neuropathic pain, and pathological crying which may occur following cerebral damage.
• 3.0 CLINICAL EFFECTS
• 3.1 SUMMARY OF EXPOSURE
• A. OVERDOSE EFFECTS -
• 1. Several reports of overdose with citalopram have resulted in death following doses greater than 2000 mg. Toxic effects have included seizures, serotonin syndrome, cardiovascular effects of prolonged QTc interval.
• B. ADVERSE EFFECTS -
• 1. Nausea, vomiting, and xerostomia were frequent adverse effects reported during therapeutic use.
• 2. CNS adverse effects have included headache, insomnia, tremor, dizziness, restlessness, and sedation.
• 3.4 HEENT
• 3.4.3 EYES
• A. In a meta-analysis of clinical studies (n=746), disturbances in accommodation were reported in approximately 9% of depressed patients (Milne & Goa, 1991).
• 3.5 CARDIOVASCULAR
• 3.5.1 SUMMARY
• A. ECG abnormalities, including QTc prolongation, have occurred following severe citalopram overdose.
• 3.5.2 CLINICAL EFFECTS
• A. ECG ABNORMAL
• 1. OVERDOSE EFFECTS
• a. Although ECG abnormalities appear less frequent with therapeutic citalopram use than with tricyclic antidepressants, QTc prolongation, sinus tachycardia, and inferolateral repolarization abnormalities have been reported in overdose (Grundemar et al, 1997; Personne et al, 1997).
• b. Widened QRS complexes were observed at doses above 600 mg (15 to 30 times the usual therapeutic dose) (Power, 1998; Grundemar et al, 1997).
• c. CASE REPORTS - Grundemar et al (1997) reported five cases (all cases) of QTc prolongation and sinus tachycardia following severe non-fatal citalopram overdoses (range 400 mg to 5200 mg).
• d. CASE SERIES - In a review of 108 cases of citalopram overdose, approximately 25% of the patients had ECG changes such as non-specific changes of the ST-T region and moderate widening of the ECG complexes, however, no clinically significant arrhythmias were reported (Personne et al, 1997).
• B. HYPOTENSION
• 1. OVERDOSE EFFECTS
• a. Hypotension has been reported following non-fatal citalopram overdose (range 400 mg to 5200 mg) in 4 patients (Grundemar et al, 1997).
• C. TACHYCARDIA
• 1. OVERDOSE EFFECTS
• a. Sinus tachycardia has been reported in 4 cases of non-fatal citalopram overdose (range 400 mg to 5200 mg) (Grundemar et al, 1997).
• D. BRADYCARDIA
• 1. ADVERSE EFFECTS
• a. Further declines in heart rate have occurred infrequently following therapeutic citalopram use in patients that had pretreatment heart rates of 48 to 60 beats/minute (Nyth et al, 1992; Nyth & Gottfries, 1990).
• 3.7 NEUROLOGIC
• 3.7.1 SUMMARY
• A. Seizures have occurred following overdose with citalopram and appear to be dose-dependent. Rarely, fatal serotonin syndrome has occurred following intentional overdose of citalopram and moclobemide.
• 3.7.2 CLINICAL EFFECTS
• A. SEIZURES
• 1. OVERDOSE EFFECTS
• a. In a review of 108 cases of citalopram overdose, seizures developed at doses greater than 600 mg (Personne et al, 1997). Grundemar et al (1997) reported generalized seizures following a non-fatal exposure of 400 mg in a 26-year-old female.
• b. INCIDENCE - At doses of 600 mg to 1900 mg 18% of the patients (six of 34 patients) developed seizures while the frequency increased to 47% (9 of 19 patients) at doses of 1900 mg to 5200 mg (Personne et al, 1997).
• B. SEROTONIN SYNDROME
• 1. OVERDOSE EFFECTS
• a. Three cases of fatal serotonin syndrome (tremor, hyperpyrexia, and seizures) occurred following overdoses involving citalopram and moclobemide. The three males died within 3 to 16 hours after overdose (Neuvonen et al, 1993).
• (1) Citalopram serum concentration was at a therapeutic level in one patient and 2 and 5 times therapeutic levels in the other cases.
• (2) Moclobemide serum concentrations were 5 times therapeutic levels in one patient and 20 to 50 times higher in the other two cases.
• b. CASE REPORT - A 58-year-old female developed mild symptoms of serotonin syndrome (anxiety, nausea, tremor, muscle rigidity) following an inadvertent dose of 100 milligrams (Moyer et al, 2000). Symptoms began within 2 hours of ingestion; staggering gait ataxia was the only residual symptom reported 5 days after exposure.
• C. SOMNOLENCE
• 1. Somnolence has been reported after therapeutic use and in overdose (de Wilde et al, 1985; Nyth et al, 1992; Milne & Goa, 1991; Personne et al, 1997; Grundemar et al, 1997).
• 2. OVERDOSE EFFECTS
• a. CASE REPORT - A 44-year-old male developed somnolence along with prolonged QTc following an overdose of 3640 mg of citalopram (Grundemar et al, 1997).
• b. CASE SERIES - At doses below 600 mg (n=41) mild symptoms of drowsiness and somnolence were observed (Personne et al, 1997).
• D. CNS EFFECTS
• 1. OVERDOSE EFFECTS
• a. In a case series of citalopram overdoses (n=108), mild symptoms of dizziness and tremor were observed at doses below 600 mg (Personne et al, 1997).
• 2. ADVERSE EFFECTS
• a. Headache (18% of patients), insomnia (15%), tremor (16%), dizziness (14%), restlessness (10%), and sedation (15%) have been commonly reported during clinical studies with citalopram (de Wilde et al, 1985; Nyth et al, 1992; Bouchard et al, 1987; Grave et al, 1987; Milne & Goa, 1991).
• 3.8 GASTROINTESTINAL
• 3.8.1 SUMMARY
• A. Nausea and vomiting have been commonly reported with citalopram therapy.
• 3.8.2 CLINICAL EFFECTS
• A. NAUSEA VOMITING
• 1. Nausea has been reported with therapeutic use and following overdose Milne & Goa, 1991; Personne et al, 1997).
• 2. ADVERSE EFFECTS
• a. In a meta-analysis of citalopram therapy, nausea (20% of patients), vomiting (20%), xerostomia (17%) and constipation (13%) were the most frequently reported gastrointestinal effects (Milne & Goa, 1991)
• B. ANOREXIA
• 1. ADVERSE EFFECTS
• a. Anorexia and dyspepsia have been reported less frequently following citalopram therapy (Bouchard et al, 1987; Milne & Goa, 1991).
• 3.9 HEPATIC
• 3.9.1 SUMMARY
• A. Abnormal hepatic function tests have occurred during therapeutic use.
• 3.9.2 CLINICAL EFFECTS
• A. HEPATIC FUNCTION ABNORMAL
• 1. ADVERSE EFFECTS
• a. Several patients have developed abnormal liver function tests after receiving citalopram during therapeutic use (Pedersen et al, 1982; de Wilde et al, 1985).
• b. LACK OF EFFECT - In a meta-analysis of clinical studies with citalopram, no significant changes in liver enzymes were reported (Milne & Goa, 1991).
• 3.10 GENITOURINARY
• 3.10.2 CLINICAL EFFECTS
• A. DYSURIA
• 1. ADVERSE EFFECTS
• a. Urination difficulties have been reported infrequently in clinical studies (Pedersen et al, 1982; Burrows et al, 1988).
• 3.11 ACID-BASE
• 3.11.2 CLINICAL EFFECTS
• A. ACIDOSIS
• 1. OVERDOSE EFFECTS
• a. Metabolic acidosis has been reported following 2 cases of non-fatal citalopram (range 1680 mg to 5200 mg) overdose (Grundemar et al, 1997). Both patients developed seizures and hypotension.
• 3.12 FLUID-ELECTROLYTE
• 3.12.2 CLINICAL EFFECTS
• A. HYPOKALEMIA
• 1. OVERDOSE EFFECTS
• a. Hypokalemia (1.8 mmol/L) was reported in a 41-year-old male following a severe non-fatal citalopram (5200 mg dose) overdose (Grundemar et al, 1997).
• 3.14 DERMATOLOGIC
• 3.14.2 CLINICAL EFFECTS
• A. SWEATING INCREASED
• 1. ADVERSE EFFECTS
• a. Diaphoresis has been commonly reported following citalopram therapy (Gravem et al, 1987; Milne & Goa, 1991; de Wilde et al, 1985; Bouchard et al, 1987).
• b. INCIDENCE - Approximately 18% of patients reported diaphoresis, as described in a meta-analysis of adverse effects experienced with citalopram (Milne & Goa, 1991).
• B. RASH
• 1. ADVERSE EFFECTS
• a. Rash has been reported infrequently following therapeutic citalopram use (Bouchard et al, 1987; Gravem et al, 1987).
• 3.15 MUSCULOSKELETAL
• 3.15.2 CLINICAL EFFECTS
• A. RHABDOMYOLYSIS
• 1. OVERDOSE EFFECTS
• a. Rhabdomyolysis developed in 2 non-fatal overdose cases (range 3640 mg to 5200 mg). The authors provided no further data, one patient did experience seizures following overdose (Grundemar et al, 1997).
• 3.18 PSYCHIATRIC
• 3.18.2 CLINICAL EFFECTS
• A. ANXIETY
• 1. ADVERSE EFFECTS
• a. Burrows et al (1988) reported that a frequent adverse effect of citalopram therapy was an agitation-anxiety syndrome (possibly akathisia).
• 3.23 OTHER
• 3.23.2 CLINICAL EFFECTS
• A. DRUG INTERACTION
• 1. TRAMADOL - The risk of seizures may be enhanced when citalopram and tramadol are coadministered. Tramadol inhibits norepinephrine and serotonin reuptake (Olin, 1995).
• 2. MOCLOBEMIDE - Fatal serotonin syndrome has been reported following coingestion of citalopram and moclobemide during overdose (Neuvonen et al, 1993).
• B. SEROTONIN SYNDROME
• 1. OVERDOSE EFFECTS
• a. Three cases of fatal serotonin syndrome (tremor, hyperpyrexia, and seizures) occurred following overdoses involving citalopram and moclobemide. The three males died within 3 to 16 hours after overdose (Neuvonen et al, 1993).
• (1) Citalopram serum concentration was at a therapeutic level in one patient and 2 and 5 times therapeutic levels in the other cases.
• (2) Moclobemide serum concentrations were 5 times therapeutic levels in one patient and 20 to 50 times higher in the other two cases.
• C. ANTICHOLINERGIC SYNDROME
• 1. ADVERSE EFFECTS
• a. Although not anticipated, anticholinergic symptoms (dry mouth, blurred vision, urination difficulties) have been reported with therapeutic use of citalopram (Burrows, et al, 1988).
• 4.0 LABORATORY/MONITORING
• 4.1 MONITORING PARAMETERS/LEVELS
• 4.1.2 SERUM/BLOOD
• A. BLOOD/SERUM CHEMISTRY
• 1. Monitor CBC, urinalysis, and liver and kidney function tests in patients with significant exposure.
• 2. Monitor fluid status and creatine kinase (CK) enzymes after significant overdose; rhabdomyolysis has developed.
• 3. Monitor serum electrolytes (including potassium, bicarbonate) following significant overdose.
• 4.1.4 OTHER
• A. ECG
• 1. Obtain baseline ECG, continuous cardiac monitoring and serial ECGs following a significant exposure or as indicated.
• B. EEG
• 1. EEG may be indicated in patients who develop seizure activity or altered mental status.
• 4.3 METHODS
• A. CHROMATOGRAPHY
• 1. Oyehaug & Ostensen (1984) have described the use of high-performance liquid chromatographic determination for citalopram and its metabolites in plasma and urine samples.
• 6.0 TREATMENT
• 6.1 LIFE SUPPORT
• A. Support respiratory and cardiovascular function.
• 6.3 PATIENT DISPOSITION
• 6.3.1 DISPOSITION/ORAL EXPOSURE
• 6.3.1.1 ADMISSION CRITERIA/ORAL
• A. Admit patients with significant clinical effects including seizures or persistent lethargy or tachycardia.
• 6.5 ORAL EXPOSURE
• 6.5.1 PREVENTION OF ABSORPTION/PREHOSPITAL
• A. EMESIS/NOT RECOMMENDED -
• 1. EMESIS: Ipecac-induced emesis is not recommended because of the potential for CNS depression and seizures.
• B. ACTIVATED CHARCOAL -
• 1. PREHOSPITAL ACTIVATED CHARCOAL ADMINISTRATION
• a. Consider prehospital administration of activated charcoal as an aqueous slurry in patients with a potentially toxic ingestion who are awake and able to protect their airway. Activated charcoal is most effective when administered within one hour of ingestion.
• (1) In patients who are at risk for the abrupt onset of seizures or mental status depression, activated charcoal should be administered by medical or paramedical personnel capable of airway management to prevent aspiration in the event of spontaneous emesis.
• 2. CHARCOAL DOSE
• a. Use a minimum of 240 milliliters of water per 30 grams charcoal (FDA, 1985). Optimum dose not established; usual dose is 25 to 100 grams in adults and adolescents; 25 to 50 grams in children aged 1 to 12 years; and 1 gram/kilogram in infants up to 1 year old (USP DI, 2000; Chyka & Seger, 1997).
• (1) Routine use of a cathartic with activated charcoal is NOT recommended as there is no evidence that cathartics reduce drug absorption and cathartics are known to cause adverse effects such as nausea, vomiting, abdominal cramps, electrolyte imbalances and occasionally hypotension (Barceloux et al, 1997).
• b. ADVERSE EFFECTS/CONTRAINDICATIONS
• (1) Complications: emesis, aspiration (Chyka & Seger, 1997). Refer to the ACTIVATED CHARCOAL/TREATMENT management for further information.
• (2) Contraindications: unprotected airway, gastrointestinal tract not anatomically intact, therapy may increase the risk or severity of aspiration; ingestion of most hydrocarbons (Chyka & Seger, 1997).
• 6.5.2 PREVENTION OF ABSORPTION
• A. GASTRIC LAVAGE
• 1. INDICATIONS: Consider gastric lavage with a large-bore orogastric tube (ADULT: 36 to 40 French or 30 English gauge tube {external diameter 12 to 13.3 mm}; CHILD: 24 to 28 French {diameter 7.8 to 9.3 mm}) after a potentially life threatening ingestion if it can be performed soon after ingestion (generally within 60 minutes).
• a. Consider lavage more than 60 minutes after ingestion of sustained-release formulations and substances known to form bezoars or concretions.
• 2. PRECAUTIONS:
• a. SEIZURE CONTROL: Is mandatory prior to gastric lavage.
• b. AIRWAY PROTECTION: Alert patients - place in Trendelenburg and left lateral decubitus position, with suction available. Obtunded or unconscious patients - cuffed endotracheal intubation.
• 3. LAVAGE FLUID:
• a. Use small aliquots of liquid. Lavage with 150 to 200 milliliters warm tap water (preferably 38 degrees Celsius) or saline per wash (in children over 5 or adults) and 10 milliliters/kilogram body weight of normal saline in young children. Continue until lavage return is clear.
• b. The volume of lavage return should approximate amount of fluid given to avoid fluid-electrolyte imbalance.
• c. CAUTION: Water should be avoided in young children because of the risk of electrolyte imbalance and water intoxication. Warm fluids avoid the risk of hypothermia in very young children and the elderly.
• 4. COMPLICATIONS:
• a. Complications of gastric lavage have included: aspiration pneumonia, hypoxia, hypercapnia, mechanical injury to the throat, esophagus, or stomach, fluid and electrolyte imbalance (Vale, 1997). Combative patients may be at greater risk for complications.
• b. Gastric lavage can cause significant morbidity; it should NOT be performed routinely in all poisoned patients (Vale, 1997).
• 5. CONTRAINDICATIONS:
• a. Loss of airway protective reflexes or decreased level of consciousness if patient is not intubated, following ingestion of corrosive substances, hydrocarbons (high aspiration potential), patients at risk of hemorrhage or gastrointestinal perforation, or trivial or non-toxic ingestion.
• B. ACTIVATED CHARCOAL
• 1. CHARCOAL ADMINISTRATION
• a. Consider administration of activated charcoal after a potentially toxic ingestion (Chyka & Seger, 1997). Administer charcoal as an aqueous slurry; most effective when administered within one hour of ingestion.
• 2. CHARCOAL DOSE
• a. Use a minimum of 240 milliliters of water per 30 grams charcoal (FDA, 1985). Optimum dose not established; usual dose is 25 to 100 grams in adults and adolescents; 25 to 50 grams in children aged 1 to 12 years; and 1 gram/kilogram in infants up to 1 year old (USP DI, 2000; Chyka & Seger, 1997).
• (1) Routine use of a cathartic with activated charcoal is NOT recommended as there is no evidence that cathartics reduce drug absorption and cathartics are known to cause adverse effects such as nausea, vomiting, abdominal cramps, electrolyte imbalances and occasionally hypotension (Barceloux et al, 1997).
• b. ADVERSE EFFECTS/CONTRAINDICATIONS
• (1) Complications: emesis, aspiration (Chyka & Seger, 1997). Refer to the ACTIVATED CHARCOAL/TREATMENT management for further information.
• (2) Contraindications: unprotected airway, gastrointestinal tract not anatomically intact, therapy may increase the risk or severity of aspiration; ingestion of most hydrocarbons (Chyka & Seger, 1997).
• 6.5.3 TREATMENT
• A. SEIZURES
• 1. SUMMARY
• a. Attempt initial control with a benzodiazepine (diazepam or lorazepam). If seizures persist or recur administer phenobarbital. Benzodiazepines and barbiturates are generally preferred over phenytoin for the control of overdose or withdrawal related seizures.
• b. Monitor for respiratory depression, hypotension, dysrhythmias, and the need for endotracheal intubation.
• c. Evaluate for hypoxia, electrolyte disturbances, and hypoglycemia (or treat with intravenous dextrose ADULT: 50 milliliters IV, CHILD: 2 milliliters/kilogram 25% dextrose).
• 2. DIAZEPAM
• a. MAXIMUM RATE: Administer diazepam intravenously over 2 to 3 minutes (maximum rate = 5 milligrams/minute).
• b. ADULT DIAZEPAM DOSE: 5 to 10 milligrams initially, repeat every 5 to 10 minutes as needed. Monitor for hypotension, respiratory depression and the need for endotracheal intubation. Consider a second agent if seizures persist or recur after diazepam 30 milligrams.
• c. PEDIATRIC DIAZEPAM DOSE: 0.2 to 0.5 milligram per kilogram repeat every 5 minutes as needed. Monitor for hypotension, respiratory depression and the need for endotracheal intubation. Consider a second agent if seizures persist or recur after diazepam 10 milligrams in children over 5 years or 5 milligrams in children under 5 years of age.
• d. RECTAL USE: If an intravenous line cannot be established, diazepam may be given per rectum (generally use twice the usual initial dose because of decreased absorption), or lorazepam may be given intramuscularly.
• e. MIDAZOLAM: has been used intramuscularly and intranasally, particularly in children when intravenous access has not been established. PEDIATRIC MIDAZOLAM DOSE: INTRAMUSCULAR: 0.2 milligram/kilogram (maximum 7 milligrams) (Chamberlain et al, 1997); INTRANASAL: 0.2 milligram/kilogram (Lahat et al, 2000). Buccal midazolam, 10 milligrams, has been used in adolescents and older children (5-years-old or more) to control seizures when intravenous access was not established (Scott et al, 1999).
• 3. LORAZEPAM
• a. MAXIMUM RATE: The rate of intravenous administration of lorazepam should not exceed 2 milligrams/minute (Prod Info Ativan(R), 1999).
• b. ADULT LORAZEPAM DOSE: 2 to 8 milligrams intravenously. Initial doses may be repeated in 10 to 15 minutes if seizures persist (Prod Info, Ativan(R), 1999; AMA, 1991).
• c. PEDIATRIC LORAZEPAM DOSE: 0.05 to 0.1 milligram/kilogram intravenously, (maximum 4 milligrams/dose) repeated twice at intervals of 10 to 15 minutes (Benitz & Tatro, 1995).
• 4. PHENOBARBITAL
• a. ADULT PHENOBARBITAL LOADING DOSE: 600 to 1200 milligrams of phenobarbital intravenously initially (10 to 20 milligrams per kilogram) diluted in 60 milliliters of 0.9 percent saline given at 25 to 50 milligrams per minute.
• b. ADULT PHENOBARBITAL MAINTENANCE DOSE: Additional doses of 120 to 240 milligrams may be given every 20 minutes.
• c. MAXIMUM SAFE ADULT PHENOBARBITAL DOSE: No maximum safe dose has been established. Patients in status epilepticus have received as much as 100 milligrams/minute until seizure control was achieved.
• d. PEDIATRIC PHENOBARBITAL LOADING DOSE: 15 to 20 milligrams per kilogram of phenobarbital intravenously at a rate of 25 to 50 milligrams per minute.
• e. PEDIATRIC PHENOBARBITAL MAINTENANCE DOSE: Repeat doses of 5 to 10 milligrams per kilogram may be given every 20 minutes.