Note: This document contains side effect information about baclofen. Some dosage forms listed on this page may not apply to the brand name Fleqsuvy.
Applies to baclofen: oral packet, oral solution, oral suspension, oral tablet. Other dosage forms:
- intrathecal solution
Serious side effects of Fleqsuvy
Along with its needed effects, baclofen (the active ingredient contained in Fleqsuvy) 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 immediately if any of the following side effects occur while taking baclofen:
Less common or rare
- Bloody or dark urine
- chest pain
- clumsiness, unsteadiness, trembling, or other problems with muscle control
- fainting
- false sense of well-being
- mental depression or other mood changes
- pounding heartbeat
- ringing or buzzing in the ears
- seeing or hearing things that are not there
- skin rash or itching
- slurred speech or other speech problems
- swelling of the ankles
- unexplained muscle stiffness
- unusual excitement
Get emergency help immediately if any of the following symptoms of overdose occur while taking baclofen:
Symptoms of overdose
- Blurred vision
- dizziness
- drowsiness
- irregular, fast or slow, or shallow breathing
- lightheadedness
- loss of strength or energy
- muscle pain or weakness
- pale or blue lips, fingernails, or skin
- seizures
- sleepiness or unusual drowsiness
- trouble breathing
- unusual weak feeling
Other side effects of Fleqsuvy
Some side effects of baclofen 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:
More common
- Confusion
- constipation
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
- headache
- increased need to urinate
- nausea
- passing urine more often
- sweating
- trouble sleeping
- unusual tiredness or weakness
Less common or rare
- Diarrhea
- loss of appetite
- muscle or joint pain
- numbness or tingling in the hands or feet
- stomach pain or discomfort
- stuffy nose
- weight gain
For Healthcare Professionals
Applies to baclofen: compounding powder, intrathecal solution, oral granule, oral liquid, oral suspension, oral tablet.
Cardiovascular
Common (1% to 10%): Cardiac output decreased, hypotension, hypertension, diminished cardiovascular functions, peripheral edema
Rare (less than 0.1%): Arrhythmias, palpitations, chest pain
Frequency not reported: Bradycardia, orthostatic hypotension[Ref]
Dermatologic
Common (1% to 10%): Rash, hyperhidrosis, urticaria/pruritus, facial edema
Uncommon (0.1% to 1%): Alopecia, diaphoresis
Frequency not reported: Rash, sweating, contact dermatitis, skin ulcer[Ref]
Endocrine
Common (1% to 10%): Ovarian cysts are palpable in 4% of women treated with for up to one year[Ref]
Gastrointestinal
Very common (10% or more): Nausea (especially at start of therapy) (up to 11%)
Common (1% to 10%): Dry mouth, GI disorder/disturbance, constipation, diarrhea, retching, vomiting, increased salivation
Uncommon (0.1% to 1%): Dysphagia, dehydration, ileus, decreased taste sensation
Rare (less than 0.1%): Colicky abdominal pain, anorexia
Frequency not reported: GI hemorrhage[Ref]
Genitourinary
Very common (10% or more): Urinary retention (up to 12%)
Common (1% to 10%): Urinary incontinence, urination impaired, sexual dysfunction, urinary frequency, enuresis, dysuria
Rare (less than 0.1%): Erectile dysfunction
Frequency not reported: Dysuria, abnormal ejaculation, oliguria, vaginitis[Ref]
Hematologic
Frequency not reported: Leukocytosis, petechial rash[Ref]
Hepatic
Rare (less than 0.1%): Disorders of hepatic function (e.g., increased AST)[Ref]
Immunologic
Common (1% to 10%): Pneumonia
Uncommon (0.1% to 1%): Septicemia[Ref]
Metabolic
Common (1% to 10%): Decreased appetite
Frequency not reported: Blood glucose increased[Ref]
Musculoskeletal
Very common (10% or more): Hypotonia (up to 52%), lower extremity weakness (up to 15%), disturbances of gait and balance
Common (1% to 10%): Muscular weakness, myalgia, upper extremity weakness, back pain, muscular hypertonia[Ref]
Nervous system
Very common (10% or more): Somnolence (up to 28%), drowsiness (up to 18%), headache (up to 16%), seizures (especially on discontinuation of therapy) (up to 15%), sedation, dizziness (up to 12%)
Common (1% to 10%): Fatigue, ataxia, tremor, lightheadedness, lassitude, exhaustion, numbness/itching/tingling, slurred speech, lethargy, hypertonia, paresthesia
Rare (less than 0.1%): Dysarthria, dysgeusia, syncope, dyskinesia, coma, potentially life-threatening withdrawal symptoms (as a result of sudden interruption of drug delivery)[Ref]
Other
Common (1% to 10%): Tinnitus, pain, asthenia
Uncommon (0.1% to 1%): Accidental injury, weight loss
Very rare (less than 0.01%): Hypothermia
Frequency not reported: Drug withdrawal syndrome
Uncommon (0.1% to 1%): Subdural hemorrhage, accidental injury, weight loss[Ref]
Ocular
Common (1% to 10%): Nystagmus, visual impairment, accommodation disorder, blurred vision, double vision, amblyopia[Ref]
Psychiatric
Common (1% to 10%): Confusional state, hallucination, depression, insomnia, euphoric mood, nightmare, personality changes
Uncommon (0.1% to 1%): Memory loss/impairment, suicidal ideation, attempted suicide
Rare (less than 0.1%): Excitement[Ref]
Renal
Very rare (less than 0.01%): Kidney calculus[Ref]
Respiratory
Common (1% to 10%): Respiratory depression, hypoventilation, dyspnea, bradypnea, feeling of pressure in the chest[Ref]