Baclo

Generic Name: Baclofen
Product Name: Baclo

Indication

Baclo (baclofen) belongs to a class of drugs called muscle relaxants and is used to relieve muscle spasms or excess tension associated with disorders such as multiple sclerosis and diseases and injuries of the spinal cord. Multiple sclerosis is a disease associated with loss of conducting layers (myelin) of nerves in the brain and spinal cord which causes a number of neurological problems. Spinal cord disease on the other hand can result from trauma, infections, degeneration or tumours which interfere with muscle and bladder function. In these conditions Baclo relieves muscle tension and pain and can help increase your mobility and ability to perform daily activities.

There are numerous other disorders such as Parkinson’s disease, stroke, cerebral palsy and rheumatoid disorders, associated with spasticity. However, Baclo is NOT appropriate in these disorders.

Action

Baclo is an antispastic agent that acts on the spinal cord as well as centrally to cause CNS depression. Baclo works by binding certain receptors called GABA_B receptors in the body. This inhibits the release of excitatory agents that are involved in muscle contraction and spasm. Hence, Baclo reduces painful spasm in the aforementioned conditions.

Dose advice

Before taking Baclo you should tell your doctor:

1. If you are pregnant or intend on becoming pregnant- Baclo is not recommended during pregnancy as animal studies have shown adverse effects on the fetus and there is limited experience in this group
2. If you have any other medical conditions- In particular tell your doctor if you have any psychiatric illness, epilepsy, peptic ulceration, cerebrovascular disease, hypertension, lung, liver or renal problems, porphyrias, alcoholism or diabetes mellitus as these can increase your risk of seide effects.
3. If you are allergic to any medications, foods or dyes- Baclo is contraindicated in patients with an allergy to Baclofen or any of the inactive ingredients of the tablets (including lactose, maize starch, microcrystalline cellulose and magnesium stearate).
4. Any other medications you are taking (including those bought from supermarkets or the chemist)- Baclo can react with some medicines used to treat depression and lower blood pressure.

Dosage

Baclo comes as white tablets containing either 10mg or 25mg of the active ingredient Baclofen. Tablets come in bottles of 100 and are designed to be taken with meals with a glass of water. Treatment with Baclo should always be commenced in hospital. You will be started on small doses (usually 5mg three times per day) which will be increased in small increments every three or so days. Your doctor will try to get the ideal dose that relieves your spasticity but still maintains enough tone in your muscles so you can do voluntary movements (such as lifting) and avoids adverse effects. The usual dosage range is 30-75mg daily but sometime up to 100mg is needed. If you are younger than 16, older than 65 or have kidney disease you may require a smaller dose with less frequent dose increases to avoid side effects. You should always take Baclo as prescribed by your doctor and should not cease the drug suddenly as it can induce withdrawal symptoms (including anxiety, altered mental status, seizures (including status epilepticus), high fever and rebound spasticity). Your doctor will discuss an appropriate duration of treatment and monitor your progress throughout. Whilst taking Baclo it is important to avoid alcohol as this can increase side effects. In addition, you should be careful driving and operating machinery as Baclo can cause drowsiness, dizziness and blurred vision. You should avoid these activities until you are certain of the effects this medication has on you.

Schedule

S4 (prescription required).

Common side effects

Like all medications, Baclo can cause side effects in some patients. Most of these will occur at the start of treatment or in patients treated with large doses and diminish over time. Very rarely will they be so severe that you require withdrawal of the medication. Elderly patients and those with other health problems (such as kidney failure) are at greater risk of side effects. The most commonly reported side effects of Baclo are listed below but if you experience any symptoms that are worrying you be sure to discuss them with your doctor. The following side effects occur in approximately 1-10% of patients:

• Nausea (feeling sick)- Very common at the start of treatment and affecting more than 10% of patients.
• Vomiting.
• Constipation.
• Diarrhoea.
• Rash, itching and excessive sweating.
• Hypotension.
• Respiratory depression.
• Myalgia and muscle weakness.
• Drowsiness.
• Dizziness.
• Headache.
• Mental confusion.
• Depression.
• CNS disorders- Seizures, tremor, problems with coordination and balance or hallucinations.
• Sleep disturbances and nightmares.
• Visual disturbances and nystagmus (oscilating eye movements).
• Tinnitus (ringing in the ears).
• Urinary disorders (dysuria/urine frequency and enuresis).

Uncommon side effects

A small number of patients may experience more serious side effects that require medical attention. The following serious side effects can occur:

• Allergic reactions- If you notice rash, itching or hives on the skin, swelling of the face, lips, tongue or other parts of the body (angioedema) of shortness of breath or wheezing see your doctor immediately.
• Respiratory depression- As Baclo causes CNS depression, when taken in large doses it can slow breathing and in extreme circumstances may lead to coma.
• Cardiovascular problem- You may notice palpitaions, irregular heart beat, ankle swelling or chest pain if this medication affects your heart.
• Severe depression or mood changes.

Note that the above lists of side effects are not necessarily exhaustive and other side effects may be discovered as more patients use the drug. However, you should not be too alarmed by these long lists as most patients will not experience any side-effects at all. It is important for you to weigh up the risks and benefits of the drug (with the advice of your doctor) in your individual case to decide if this drug is suited for you.

References

1. Australian Medicines Handbook- 16.9 Baclofen. AMH Pty Ltd. 2006.
2. Baclo- Consumer Medicine Information, Douglas Pharmaceuticals Australia Limited, 2001. Available at: [URL Link]
3. MIMS online- Prescribing Information. Baclo. MIMS Australia Pty Ltd 2003.

For further information talk to your doctor.