Summary

Commonly reported side effects of midazolam include: apnea and bradypnea. Other side effects include: variable blood pressure. Continue reading for a comprehensive list of adverse effects.

Applies to midazolam: injection solution. Other dosage forms:

• nasal spray
• oral syrup

Serious side effects of Midazolam

Along with its needed effects, midazolam may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking midazolam:

Less common

• Aggressiveness
• agitation
• anxiety
• choking
• confusion
• decreased awareness or responsiveness
• decreased urine output
• difficulty walking, speaking, or writing
• discouragement
• dizziness
• feeling sad or empty
• fever
• headache
• irritability
• lack of appetite
• loss of bladder or bowel control
• loss of consciousness
• loss of interest or pleasure
• memory loss
• muscle twitching
• nausea
• nightmares or unusually vivid dreams
• rapid weight gain
• seizures
• severe sleepiness
• strong urge to urinate
• swelling of the face, ankles, or hands
• thirst
• trouble concentrating
• trouble sleeping
• trouble breathing
• unable to speak
• unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness

Get emergency help immediately if any of the following symptoms of overdose occur while taking midazolam:

Symptoms of overdose

• Agitation
• changes in patterns and rhythms of speech
• confusion
• excitement
• irritability
• lack of coordination
• loss of strength or energy
• muscle pain or weakness
• relaxed and calm feeling
• restlessness
• shakiness and unsteady walk
• slurred speech
• talkativeness
• trouble in speaking
• unsteadiness, trembling, or other problems with muscle control or coordination
• unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness
• unusual weak feeling

Other side effects of Midazolam

Some side effects of midazolam may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

• Bleeding, blistering, burning, coldness, discoloration of skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site

Rare

• Muscle stiffness

For Healthcare Professionals

Applies to midazolam: compounding powder, injectable solution, intramuscular solution, intravenous solution, nasal spray, oral syrup.

General

The most commonly reported side effects with oral formulations include emesis and nausea. Decreased tidal volume/respiratory rate and apnea were most commonly reported with parenteral formulations.^[Ref]

Respiratory

Oral:

Very common (10% or more): Respiratory adverse events (up to 11%)

Common (1% to 10%): Respiratory depression, hypoxia, laryngospasm, upper airway obstruction, rhonchi, congestion

Uncommon (0.1% to 1%): Sneezing/rhinorrhea

Frequency not reported: Apnea, hypercarbia, desaturation, stridor, hiccough

Parenteral:

Very common (10% or more): Decreased tidal volume/respiratory rate (up to 23.3%), apnea (up to 15.4%)

Common (1% to 10%): Hiccoughs, coughing, desaturation

Very rare (less than 0.01%): Dyspnea, hiccup, laryngospasm, respiratory arrest

Frequency not reported: Respiratory depression

Postmarketing reports: Bronchospasm, hyperventilation, wheezing, shallow respirations, airway obstruction, tachypnea, dysphonia, yawning, continued phonation^[Ref]

Respiratory adverse events included hypoxia, laryngospasm, rhonchi, coughing, respiratory depression, airway obstruction, upper airway congestion, and shallow respirations; these side effects occurred more frequently at higher doses.

Decreased tidal volume/respiratory rate occurred in 23.3% of patients given IV formulations and in 10.8% of patients given IM formulations.

Apnea occurred in 15.4% of patients given IV formulations.^[Ref]

Gastrointestinal

Oral:

Very common (10% or more): Emesis/vomiting (up to 11%)

Common (1% to 10%): Nausea

Frequency not reported: Gagging, salivation

Parenteral:

Common (1% to 10%): Nausea, vomiting

Very rare (less than 0.01%): Constipation, dry mouth

Postmarketing reports: Acid taste, excessive salivation, retching, toothache^[Ref]

Nervous system

Oral:

Common (1% to 10%): Sedation/prolonged sedation, somnolence, depressed levels of consciousness

Frequency not reported: Drooling, dizziness, ataxia, vertigo, dysarthria, loss of balance

Parenteral:

Common (1% to 10%): Headache, oversedation, drowsiness, seizure-like activity

Very rare (less than 0.01%): Movement disorder, ataxia, dizziness, seizure, anterograde amnesia

Frequency not reported: Involuntary movements, hyperactivity, decreased alertness, somnolence, prolonged/postoperative sedation, convulsions/drug withdrawal convulsions, feeling faint, tonic/clonic movements and muscle tremor

Postmarketing reports: Vasovagal episode, retrograde amnesia, grogginess, athetoid movements, lethargy, slurred speech, paresthesia, loss of balance, lightheadedness, feeling of burning, emergence delirium or agitation^[Ref]

Cardiovascular

Oral:

Common (1% to 10%): Bradycardia, bigeminy

Frequency not reported: Increased heart rate, cardiac arrest, heart failure, decreased systolic and diastolic blood pressure

Parenteral:

Common (1% to 10%): Hypotension

Very rare (less than 0.01%): Bradycardia, cardiac arrest, vasodilation

Frequency not reported: Thrombophlebitis, thrombosis, variations in blood pressure and pulse rate

Postmarketing reports: Bigeminy, premature ventricular contractions, tachycardia, nodal rhythm, hematoma, cardiovascular collapse, cardiovascular reactions, severe cardiorespiratory adverse events^[Ref]

Local

Parenteral:

Common (1% to 10%): IM injection site pain, IV site tenderness/pain during injection/redness/induration

Uncommon (0.1% to 1%): IM injection site induration/redness/muscle stiffness, IV site phlebitis

Frequency not reported: Injection site erythema, injection site pain

Postmarketing reports: Hive-like elevation at injection site, warmth or coldness at injection site^[Ref]

Psychiatric

Oral:

Common (1% to 10%): Agitation

Frequency not reported: Dysphoria, disinhibition, excitation, aggression, mood swings, hallucinations, confusion, inappropriate/adverse behavior, behavioral/emotional disorders, euphonia, libido disorders, restlessness, irritability, delusions, anger eruptions, nightmares, psychosis, physical dependency, withdrawal symptoms, abuse, depression (existing, unobserved depression)

Parenteral:

Very rare (less than 0.01%): Aggression/aggressiveness, agitation, anger, hallucination, hostility, confusion/confusional state, euphoric mood/euphoria

Frequency not reported: Rage, excitement/paroxysmal excitement, abuse, physical drug dependence and withdrawal syndrome

Postmarketing reports: Argumentativeness, nervousness, anxiety, restlessness, sleep disturbance, insomnia, nightmares, dysphoria, irritability, tension, mood changes, dreaming during sleep^[Ref]

Dermatologic

Oral:

Common (1% to 10%): Rash

Uncommon (0.1% to 1%): Pruritus and urticaria

Parenteral:

Frequency not reported: Angioedema

Postmarketing reports: Hives, rash, pruritus, skin reactions^[Ref]

Ocular

Oral:

Frequency not reported: Diplopia, strabismus, blurred vision

Parenteral:

Common (1% to 10%): Nystagmus

Postmarketing reports: Blurred vision, diplopia, pinpoint pupils, visual disturbance, difficulty focusing eyes, cyclic movement of the eyelids^[Ref]

Other

Oral:

Frequency not reported: Fatigue, falls

Parenteral:

Common (1% to 10%): Paradoxical reaction

Very rare (less than 0.01%): Fatigue, falls, assault/physical assault

Postmarketing reports: Prolonged emergence from anesthesia, blocked ears, chills, weakness, swelling, dreaming during emergence^[Ref]

Hypersensitivity

Oral:

Frequency not reported: Hypersensitivity

Parenteral:

Frequency not reported: Hypersensitivity, anaphylactic shock

Postmarketing reports: Allergic reaction, anaphylactoid reactions^[Ref]

Musculoskeletal

Oral:

Frequency not reported: Muscle weakness, fractures

Parenteral:

Frequency not reported: Fractures^[Ref]