eMedicine Specialties > Neurology > Neuromuscular Diseases
Schwartz-Jampel Syndrome: Treatment & Medication
Updated: Feb 2, 2007
- Overview
- Differential Diagnoses & Workup
- Treatment & Medication
- Follow-up
Treatment
Medical Care
Treatment aims to reduce the abnormal muscle activity that causes stiffness and cramping. For the specific problems of blepharospasm, blepharophimosis, and ptosis, botulinum toxin type A (BTA) (BOTOX®) therapy and surgery may also be considered.
- Nonpharmacologic modalities such as massage, warming, gradually warming-up prior to exercise, and gradual stretching may obviate the need for medications.
- This is a rare condition; the authors know of no controlled trials that have been performed.
- Medications that have been found useful in myotonic disorders, such as the anticonvulsants (eg, phenytoin, carbamazepine) and the antiarrhythmics (eg, mexiletine, procainamide, quinidine, quinine), may be tried.
- Physicians should remember that the muscle stiffness in SJS patients is not life threatening, whereas the adverse effects of these medications can be in some cases. In addition, none of the medications mentioned is approved specifically for this disease, with the exception that "skeletal muscle hyperactivity" is listed as part of the category information for quinine.
- Administering via any route other than oral is not advisable when using these medications to treat muscle stiffness associated with SJS or similar conditions. The patient should be monitored carefully for possible development of the listed adverse effects. Specifically, patients who are to receive antiarrhythmics or quinine should have no significant cardiac conduction abnormality or tendency toward any conduction abnormality. Consultation with a cardiologist should be strongly considered when prescribing these medications.
- BOTOX® injections reportedly yielded good results for relieving blepharospasm in 2 sisters with SJS (Vargel, 2006). The authors proceeded slowly and carefully, individualizing the treatment to the needs of the patients. They initially administered a total of 25 units in the orbicularis oculi of each eye. This provided no significant relief. After waiting 6 months, they doubled the dose. This began to provide relief. After waiting another 6 months, they again administered 50 units to the orbicularis oculi of each eye and the patient obtained significant cosmetic and functional improvement. Because ptosis can also be a problem in SJS patients and because BOTOX® can produce ptosis, one must proceed very carefully. Interestingly, another report indicated that giving BOTOX® just to the lower eyelid muscles had the effect of widening the aperture of the eye in persons with this condition (Flynn, 2001).
Surgical Care
For cases of blepharospasm, ptosis, and other difficulties maintaining a sufficiently wide-open eye, if BOTOX® does not work, a variety of surgical techniques have been used effectively, including orbicularis oculi myectomy, levator aponeurosis resection, and lateral canthopexy. A 2006 article describes some surgical approaches and provides additional references (Morrison, 2006).
Medication
For additional information on pharmacodynamics or pharmacokinetics of the drugs discussed in this section, standard pharmacologic references such as Drug Facts and Comparisons (Walters Kluwer, St. Louis, Mo), Mosby's GenRx (Mosby, St. Louis, Mo), Physicians Desk Reference (Medical Economics Company), or the package insert should be consulted.
Anticonvulsants
Although the primary use of anticonvulsants is to decrease excessive neuronal discharges seen in epileptic seizures, some of them appear to also reduce excess muscle cell depolarization. The fundamental mechanism in both cases may be the anticonvulsants' ability to reduce the activity of ion channels in the cell membrane. They are used widely in central pain syndromes. Their use to reduce muscle spasm and cramps is largely empirical and they are not approved by the US Food and Drug Administration for this purpose.
Phenytoin (Dilantin)
As an anticonvulsant, phenytoin reduces the rate at which neurons fire by stabilizing the inactive form of neuronal sodium channels and by blocking L-type neuronal calcium channels. May affect similar channels in muscle to reduce muscle contraction.
Adult
Seizures: 300 mg/d PO typically recommended; some authorities give maximum of 5 mg/kg/d PO If muscle contractions trouble patient at night, 100 mg hs may be sufficient; sometimes as much as 300 mg can be given as single dose hs; in other cases, must be given bid/tid
Pediatric
Seizures: 5 mg/kg/d PO bid/tid
Muscle irritability: 30 mg PO either hs or during day when child is most troubled by muscle contractions; gradually increase to 4-8 mg/kg/d divided bid/tid; if effective at low dose, do not increase dosage
Amiodarone, benzodiazepines, chloramphenicol, cimetidine, fluconazole, isoniazid, metronidazole, miconazole, phenylbutazone, succinimides, sulfonamides, omeprazole, phenacemide, disulfiram, ethanol (acute ingestion), trimethoprim, and valproic acid may increase toxicity
Barbiturates, diazoxide, ethanol (chronic ingestion), rifampin, antacids, charcoal, carbamazepine, theophylline, and sucralfate may decrease effects
May decrease effects of acetaminophen, corticosteroids, dicumarol, disopyramide, doxycycline, estrogens, haloperidol, amiodarone, carbamazepine, cardiac glycosides, quinidine, theophylline, methadone, metyrapone, mexiletine, oral contraceptives, and valproic acid
Documented hypersensitivity; Stokes-Adams syndrome; significant cardiac rhythm disturbances (eg, sinus bradycardia, sinoatrial block, second- or third-degree AV block)
Pregnancy
C - Safety for use during pregnancy has not been established.
Precautions
Death from cardiac arrest after too-rapid IV administration may occur (sometimes preceded by marked QRS widening)
Caution in acute intermittent porphyria and diabetes; discontinue drug if hepatic dysfunction occurs Can provoke reactions in several specific systems or organs, including CNS (eg, nystagmus, ataxia, slurred speech, confusion, dizziness), cardiovascular (eg, cardiac collapse, hypotension), GI (various disturbances), gingival hyperplasia, connective-tissue abnormalities, hepatitis and other liver damage, skin (rashes, other problems), endocrine (eg, increase in blood glucose, diabetes insipidus), genitourinary, hematological, respiratory, special senses, and musculoskeletal (including osteoporosis)
Perform CBC counts and urinalyses when therapy is begun and at monthly intervals for several months thereafter to monitor for blood dyscrasias
Discontinue use if rash appears; if rash is exfoliative, bullous, or purpuric, do not resume use
Carbamazepine (Tegretol)
Chemical analogue of TCAs and was first developed for depression. Was found to be useful for relief of pain in depression. Used for trigeminal neuralgia. Because trigeminal neuralgia is caused by rapid firing of nerves, it was next tried for rapid neuronal firing seen in seizures and proved very effective. Like phenytoin, probably works by inhibiting neuronal sodium channels and may have direct effects on neurotransmitter systems.
May inhibit sodium channels or other ion channels in muscle. Adult dose similar to that used in pain syndromes.
Adult
100 mg PO bid initially; increase gradually to 200 mg PO tid/qid if tolerated
Pediatric
<6 years: 10-20 mg/kg/d PO
6-12 years: 10 mg/kg/d PO initially; increase to 20-30 mg/kg/d PO divided bid/qid
If susp (liquid) form used, smaller, more frequent doses are better tolerated (ie, tid/qid)
Danazol within last 30 d may significantly increase serum levels (avoid whenever possible); do not coadminister with MAOIs; cimetidine may increase toxicity, especially if taken in first 4 wk of therapy; may decrease primidone and phenobarbital levels (coadministration may increase carbamazepine levels)
Documented hypersensitivity; history of bone marrow depression; MAOIs within last 14 d
Pregnancy
C - Safety for use during pregnancy has not been established.
Precautions
Do not use to relieve minor aches or pains; caution with increased intraocular pressure; obtain CBC counts and serum iron at baseline prior to treatment, during first 2 mo, and yearly or every other year thereafter; can cause drowsiness, dizziness, and blurred vision; caution while driving or performing other tasks requiring alertness
Antiarrhythmic agents
Cardiac antiarrhythmics reduce or regulate the firing rate of cardiac cells by a number of mechanisms, the most precisely understood of which are effects on ion channels. That a similar effect may occur in the skeletal muscle should not be surprising. Of the antiarrhythmics, mexiletine is probably the most commonly used for this condition. Procainamide and quinidine also have been listed for completeness and because they are used by many neurologists to treat muscle stiffness and muscle spasm. Quinine also can be useful occasionally. Quinine should be classified as an antiarrhythmic because of its similarity to quinidine. However, the most recent classifications list it under "antimalarials, antiprotozoals, skeletal muscle hyperactivity." It is therefore discussed under that category.
Mexiletine (Mexitil)
As class IB antiarrhythmic, preferentially binds to open or inactivated calcium channels with rapid association rate. Binding to open channels effectively shortens action potential (particularly third phase) and binding to inactivated channels maintains inactivated (refractory) state. This slows firing of cells. Presumably, similar effect may occur in skeletal muscle.
Adult
200 mg PO tid initially; increase dose by 50 or 100 mg q2-3d until 300 mg tid reached; sometimes as much as 400 mg tid used
Muscle stiffness and spasm: 150 mg PO tid initially; not advisable to increase dose to >300 mg tid
Pediatric
Not established
Aluminum-magnesium hydroxide compounds, atropine, narcotics, hydantoins, rifampin, and urinary acidifiers may decrease levels; metoclopramide and urinary alkalinizers may increase levels; cimetidine can either increase or decrease levels; may increase levels of caffeine and theophylline
Documented hypersensitivity; cardiogenic shock; second- or third-degree AV block (without pacemaker)
Pregnancy
C - Safety for use during pregnancy has not been established.
Precautions
Second- or third-degree AV block (without pacemaker) is contraindication; can be used cautiously in patients with second- or third-degree AV block with pacemaker, first-degree AV block, sinus node dysfunction, intraventricular conduction abnormalities, hypotension, or congestive heart failure (consultation with cardiologist recommended before using this medication in any of these medical conditions)
Liver injury reported, particularly in conjunction with congestive heart failure or cardiac ischemia—monitor liver enzymes; leukopenia or agranulocytosis occur rarely—CBC count should be monitored; convulsions have occurred in approximately 0.2% of patients, thus, caution indicated if patient has history of seizures; avoid other drugs that significantly modify urine pH
Procainamide (Procanbid, Pronestyl)
As class IA antiarrhythmic, blocks open or inactivated sodium channels with slower association rate than class IB drugs (eg, mexiletine). This slows depolarization phase (phase 0) of action potential and prolongs overall action potential, thus decreasing firing rate. Presumably similar effect may occur in skeletal muscle.
Has been listed because included in discussions of muscle stiffness or muscle spasm. Has never been prescribed by authors for this condition. If used for muscle stiffness, then cardiac dosing regimen should be used, starting with short-acting form. This is replaced with equivalent amount of long-acting form once medication has proven effective and is well tolerated.
Adult
Cardiac arrhythmia: 50 mg/kg/d IV q3-6h, with total dose and interval adjusted according to patient response; 250 mg IV q3h of standard form is equivalent to 500 mg q6h of SR form
Muscle stiffness: 250-500 mg IV qid
Pediatric
Not established
Cimetidine, ranitidine, beta-blockers, amiodarone, trimethoprim, and quinidine increase levels of procainamide metabolite NAPA; may increase effect of skeletal muscle relaxants quinidine and lidocaine and neuromuscular blockers; ofloxacin inhibits tubular secretion and may increase bioavailability; sparfloxacin may increase risk of cardiotoxicity
Documented hypersensitivity; second- or third-degree heart block, if pacemaker not in place; torsade de pointes; systemic lupus erythematosus
Pregnancy
C - Safety for use during pregnancy has not been established.
Precautions
Monitor for hypotension; plasma concentrations of procainamide and active metabolite, NAPA, may increase in renal failure; high or toxic concentrations may induce AV block or abnormal automaticity; caution in complete AV block, digitalis intoxication, organic heart disease, renal disease, and hepatic insufficiency
Quinidine (Cardioquin, Quinora)
As class IA antiarrhythmic, blocks open or inactivated sodium channels with slower association rate than class IB drugs (eg, mexiletine). This slows depolarization phase (phase 0) of action potential and prolongs overall action potential, thus decreasing firing rate. Presumably similar effect may occur in skeletal muscle.
For SJS, only PO administration known to be used. Use of any other mode of administration is not advised.
Adult
200 mg PO test dose administered with observation for idiosyncratic reactions
Premature atrial and ventricular contractions: 200-300 mg PO tid/qid
Pediatric
Not established
Phenytoin, rifampin, and phenobarbital may decrease concentrations; ritonavir, sparfloxacin, beta-blockers, amiodarone, verapamil, cimetidine, alkalinizing agents, or nondepolarizing and depolarizing muscle relaxants may increase toxicity; may enhance effect of anticoagulants
Documented hypersensitivity; complete AV block or intraventricular conduction defects; concurrent ritonavir or sparfloxacin
Pregnancy
X - Contraindicated in pregnancy
Precautions
Caution in G-6-PD deficiency and those with tendency to develop granulocytopenia; avoid use in myocardial depression, hepatic or renal insufficiency, and myasthenia gravis
Antimalarials, antiprotozoals, skeletal muscle hyperactivity
The only drug in this category generally used to relieve muscle stiffness is quinine. Quinine appears to increase the refractory period for muscle discharge, exerts a curarelike action on the motor endplate, and alters the intracellular calcium distribution in a way that makes the muscle less excitable.
Quinine sulfate (Formula Q)
Actually an optical isomer of quinidine and, like quinidine, belongs to cinchona alkaloid group of drugs. Also has effects on heart similar to those of quinidine and, thus, is subject to similar cautions. Available in 260-, 300-, and 325-mg cap. Any of these can be given as hs dose for nocturnal muscle stiffness.
Adult
Administer up to 650 mg PO tid; authors have not prescribed >300 mg tid for off-label use in muscle stiffness
Pediatric
Not established
Aluminum-containing antacids may delay or decrease bioavailability; cimetidine increases blood levels and creates potential for toxicity; rifamycins decrease concentrations by increasing hepatic clearance (effect can persist for several days after discontinuing rifamycins); acetazolamide or sodium bicarbonate may increase toxicity by increasing blood levels; may enhance action of warfarin and other oral anticoagulants by decreasing synthesis of vitamin K–dependent clotting factors; may increase digoxin serum concentrations—important to monitor digoxin levels periodically; may decrease plasma cholinesterase activity, causing decrease in metabolism of succinylcholine
Documented hypersensitivity; optic neuritis; tinnitus; G-6-PD deficiency; history of black water fever
Pregnancy
X - Contraindicated in pregnancy
Precautions
Caution in G-6-PD deficiency and tendency to develop granulocytopenia; prolonged treatment or overdosing may cause cinchonism; quinine has quinidinelike activity and thus can cause cardiac arrhythmias
Neuromuscular blocking agents
Indicated for blepharospasms associated with SJS.
Botulinum toxin type A (BOTOX®)
One of several toxins produced by Clostridium botulinum. Blocks neuromuscular transmission through a 3-step process, as follows:
(1) blockade of neuromuscular transmission; BTA binds to motor nerve terminal. The binding domain of the type A molecule appears to be the heavy chain, which is selective for cholinergic nerve terminals.
(2) BTA is internalized via receptor-mediated endocytosis, a process in which the plasma membrane of the nerve cell invaginates around the toxin-receptor complex, forming a toxin-containing vesicle inside nerve terminal. After internalization, the light chain of the toxin molecule, which has been demonstrated to contain the transmission-blocking domain, is released into the cytoplasm of the nerve terminal.
(3) BTA blocks acetylcholine release by cleaving SNAP-25, a cytoplasmic protein that is located on the cell membrane and that is required for the release of this transmitter. The affected terminals are inhibited from stimulating muscle contraction. Toxin does not affect
synthesis or storage of acetylcholine or conduction of electrical signals along the nerve fiber.
Typically, a 24-72 h delay occurs between administration of toxin and onset of clinical effects, which terminate in 2-6 mo. This purified neurotoxin complex is a vacuum-dried form of purified BTA, which contains 5 ng of neurotoxin complex protein per 100 U. Treats excessive, abnormal contractions associated with blepharospasm.
BTA must be reconstituted with 2 mL of 0.9% sodium chloride diluent. With this solution, each 0.1 mL results in 5 U dose. Patient should receive 5-10 injections per visit. Must be reconstituted from vacuum-dried toxin into 0.9% sterile saline without preservative using manufacturer's instructions to provide injection volume of 0.1 mL; must be used within 4 h of storage in refrigerator at 2-8°C. Preconstituted dry powder must be stored in freezer at <5°C. Reexamine patients 7-14 d after initial dose to assess for response. Increase doses 2-fold over previous one for patients experiencing incomplete paralysis of target muscle. Do not exceed 25 U when giving it as single injection or 200 U as cumulative dose in 30-day period.
Adult
25 U per eye divided into 4-6 periocular injection sites (2.5-10 U/site) may avoid adverse effects; lower volumes (higher concentrations) suggested to avoid risk of spread to adjacent areas; adjust subsequent treatments depending on response to initial doses (eg, Vargel et al increased to 50 U per eye 6 mo later when 25 U did not work); note that the 6-mo waiting period between treatment is important to reduce chances that patient develops antibodies to BTA
Pediatric
<12 years: Not established
>12 years: Administer as in adults
Aminoglycosides or drugs that interfere with neuromuscular transmission may potentiate effects of BTA
Documented hypersensitivity; infection present at injection site
Pregnancy
Precautions
Do not exceed recommended dosages and frequencies of administration; presence of antibodies to BTA may reduce effects of therapy; when used for cervical dystonia may cause dysphagia, upper respiratory tract infection, neck pain, or headache; ptosis may occur when used for blepharism or strabismus; weakness of hand muscles and blepharoptosis may occur when used for palmar or facial hyperhidrosis, respectively When used cosmetically for glabellar lines, may cause headache, respiratory tract infection, flulike syndrome, blepharoptosis, or nausea
More on Schwartz-Jampel Syndrome |
| Overview: Schwartz-Jampel Syndrome |
| Differential Diagnoses & Workup: Schwartz-Jampel Syndrome |
 Treatment & Medication: Schwartz-Jampel Syndrome |
| Follow-up: Schwartz-Jampel Syndrome |
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References
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Further Reading
Keywords
Schwartz Jampel syndrome, chondrodystrophic myotonia, myotonic myopathy, dwarfism, chondrodystrophy, ocular and facial anomalies, Schwartz-Jampel-Aberfeld syndrome, SJA syndrome, SJS
