"Nov. 2, 2012 -- Safety steps taken in the wake of the fungal meningitis outbreak have worsened drug shortages, raising questions about whether the U.S. must choose between the safety and the availability of crucial medicines.
The most commonly reported adverse events with LIORESAL Intrathecal (baclofen injection) in clinical trials were drowsiness, weakness in the lower extremities, dizziness and seizures.
Adverse drug reactions from clinical trials are listed in the table below according to system organ classes in MedDRA. Within each system organ class, the adverse drug reactions are ranked under headings of frequency, the most frequent reactions first. Within each frequency grouping, adverse drug reactions are presented in order of decreasing seriousness. In addition, the corresponding frequency category using the following convention (CIOMS III) is also provided for each adverse drug reaction: very common ( ≥ 1/10); common ( ≥ 1/100, < 1/10); uncommon ( ≥ 1/1,000, < 1/100); rare ( ≥ 1/10,000, < 1/1,000); very rare ( < 1/10,000), including isolated reports.
Adverse events associated with the delivery system (e.g. mass at the tip of the catheter, catheter dislocation with possible complications, pocket infection, meningitis, overdose due to wrong manipulation of the device) have been reported, whereby in some cases a causal relationship with baclofen cannot be excluded (see WARNINGS). These are in addition to those listed below. In a fatal case of a child (causality with baclofen uncertain), inflammatory signs in the posterior horns and signs of arachnoiditis in proximity of the catheter tip were observed. This corresponds to observations in dogs, where chronic inflammatory reactions to the foreign body of the catheter were observed, independently of baclofen concentration.
Incidence of Most Frequent Adverse Events in US
|Adverse Event||Number of patients reporting events (%)|
|Somnolence||13 (5.3%)||11(5.1%)||18 (8.4%)|
|Weakness, Lower Extremities||1 (0.4%)||11(5.1%)||15 (7.0%)|
|Dizziness||6 (2.4%)||5 (2.3%)||12(5.6%)|
|Convulsion||1 (0.4%)||4 (1.9%)||11 (5.1%)|
|Headache||0 (0%)||3 (1.4%)||9 (4.2%)|
|Nausea/Vomiting||3 (1.2%)||5 (2.3%)||3 (1.4%)|
|Numbness/Itching/Tingling||2 (0.8%)||1 (0.5%)||8 (3.7%)|
|Hypotension||3 (1.2%)||0 (0%)||5 (2.3%)|
|Vision Blurred||0 (0%)||2 (0.9%)||5 (2.3%)|
|Constipation||0 (0%)||2 (0.9%)||5 (2.3%)|
|Hypotonia||2 (0.8%)||3 (1.4%)||2 (0.9%)|
|Dysarthria||0 (0%)||1 (0.5%)||6 (2.8%)|
|Coma (Overdose)||0 (0%)||4 (1.9%)||3 (1.4%)|
|Lethargy||1 (0.4%)||0 (0%)||4 (1.9%)|
|Weakness, Upper Extremities||1 (0.4%)||0 (0%)||4 (1.9%)|
|Hypertension||1 (0.4%)||2 (0.9%)||2 (0.9%)|
|Dyspnea||1 (0.4%)||2 (0.9%)||1 (0.5%)|
In addition to the more common adverse events reported above, the following adverse events were observed during clinical trials elsewhere or reported by clinicians.
Metabolism and nutritional disorders
Common: Depression, anxiety, agitation
Uncommon: Suicide ideation and suicide attempt, hallucinations, paranoia, euphoric mood
Nervous system disorders
Rare: pulmonary embolism.
Uncommon: Deep vein thrombosis, flushing, pallor
Common: Dry mouth, diarrhea, decreased appetite, increased salivation
Respiratory, thoracic and mediastinal disorders
Common: Respiratory depression, pneumonia,
Renal and urinary disorders
Common: urinary incontinence, urinary retention.
Reproduction system and breast disorders
Common: Sexual dysfunction
Skin and subcutaneous tissue disorders
Musculoskeletal and connective tissue disorders
General disorders and administration site conditions
Common: Asthenia, pyrexia, chills, pain
Adverse Drug Reactions From Spontaneous Reports And Literature Cases (frequency not known)
The following adverse drug reactions have been derived from post-marketing experience with LIORESAL Intrathecal via spontaneous case reports and literature cases. Because these reactions are reported voluntarily from a population of uncertain size, it is not possible to reliably estimate their frequency which is therefore categorized as not known. Adverse reactions are listed according to system organ classes in MedDRA. Within each system organ class, ADRs are presented in order of decreasing seriousness.
Nervous system disorders: dysphoria
Respiratory, thoracic and mediastinal disorders: bradypnea
Read the Lioresal Intrathecal (baclofen injection) Side Effects Center for a complete guide to possible side effects
There is little experience with the use of LIORESAL Intrathecal in combination with systemic medications to predict specific drug-drug interactions, although it is suggested that the low baclofen systemic exposure observed after intrathecal administration could reduce the potential for pharmacokinetic interactions (see CLINICAL PHARMACOLOGY).
Levodopa/ Dopa Decarboxylase (DDC) inhibitor (carbidopa)
Concomitant use of oral LIORESAL and levodopa (alone or in combination with a DDC inhibitor, carbidopa) resulted in increased risk of adverse events such as visual hallucinations, confusional state, headache and nausea. Worsening of the symptoms of Parkinsonism has also been reported. Thus, similar interaction can be anticipated for intrathecal LIORESAL.
Concomitant use of intrathecal baclofen and general anesthetics (e.g. fentanyl, propofol) may increase the risk of cardiac disturbances and seizures. Thus, caution should be exercised when anesthetics are administered to patients receiving intrathecal LIORESAL.
The co-administration of other intrathecal agents with LIORESAL Intrathecal has not been tested and the safety of these combinations is unknown.
Alcohol and other compounds affecting CNS
The central nervous system depressant effects of alcohol and other compounds affecting the CNS (e.g. analgesics, neuroleptics, barbiturates, benzodiazepines, anxiolytics) may be additive to the effects of LIORESAL Intrathecal. Increased sedation may occur when LIORESAL Intrathecal is taken concomitantly with other drugs causing CNS depression, including other muscle relaxants (such as tizanidine), synthetic opiates, hypnotics, anxiolytics or alcohol (see PRECAUTIONS - Driving and using machines). The risk of respiratory depression is also increased. Careful monitoring of respiratory and cardiovascular functions is essential, especially in patients with cardiopulmonary disease and respiratory muscle weakness.
When using oral baclofen, concurrent treatment with tricyclic antidepressants may potentiate the effect of LIORESAL, resulting in pronounced muscular hypotonia. In addition, concomitant use of tricyclic antidepressants can cause sedation, drowsiness and potentiate the effects of LIORESAL resulting in pronounced muscular hypotonia. Therefore, caution is advised when using LIORESAL Intrathecal in this combination.
Concomitant use of oral baclofen and lithium resulted in aggravated hyperkinetic symptoms. Caution should be exercised when LIORESAL Intrathecal is used concomitantly with lithium.
Since concomitant treatment with oral LIORESAL and antihypertensives is likely to increase antihypertensive effects, it is recommended that blood pressure is checked and if necessary, the dosage of antihypertensive medication adjusted accordingly.
Last reviewed on RxList: 1/10/2014
This monograph has been modified to include the generic and brand name in many instances.
Additional Lioresal Intrathecal Information
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