Symmetrel (100 mg): Uses, Dosage, Benefits, Side Effects, Safety

Symmetrel 100mg contains amantadine hydrochloride which is a prescription medicine with antiviral and anti-Parkinsonian properties. Amantadine may be used in selected cases of Parkinsonism and drug-induced extrapyramidal reactions. Some formulations and labels also describe its use against influenza A . However, resistance has limited the usefulness of amantadine against many circulating influenza strains .

Since Symmetrel affects the central nervous system and is primarily excreted by the kidneys, patients should take the drug only as directed by their doctor. Here is a guide to Symmetrel 100 mg uses, dosage, benefits, side effects, precautions and important safety information.

What Is Symmetrel 100mg?

Symmetrel 100mg is a tablet that contains 100 mg of amantadine hydrochloride. Amantadine is in a group of medicines that can affect dopamine-related activity in the brain. It also has antiviral activity against influenza A, but clinical usefulness against influenza depends on susceptibility and resistance patterns of the viruses.

It is a prescription drug and is available as an oral tablet.

Uses of Symmetrel 100mg

Parkinson’s Disease and Parkinsonism

Doctors can prescribe amantadine for Parkinson’s disease and other types of Parkinsonism. Can help control movement disorder-related symptoms. The FDA label indicates that amantadine is generally less effective than levodopa in Parkinson’s disease, and the physician may select treatment according to the individual patient.

Drug-induced movement disorders

Symmetrel may have a use in treating drug-induced extrapyramidal reactions. These reactions can happen after using some medicines and can cause abnormal movements, stiffness or other motor symptoms.

Influenza type A

Amantadine has antiviral activity against influenza A . However, resistance can develop in influenza A viruses ; this reduces the effectiveness of amantadine . Therefore, healthcare professionals should consider current susceptibility information when using for influenza.

What is Symmetrel?

The exact mechanism of amantadine in Parkinson’s disease is not fully understood. Research has shown it can affect dopamine pathways and act as a weak NMDA receptor antagonist. That, in turn, may impact brain signalling that is involved in movement.

Antiviral activity of amantadine is due to inhibition of influenza A M2 protein, blocking important steps in viral replication. However, resistant influenza A variants can reduce this effect .

Symmetrel 100 mg Dosage

The right dose depends on the condition being treated, age, kidney function, other medicines and response.

The current amantadine tablet labelling lists the usual adult dose for Parkinsonism when used alone as 100 mg twice daily. Some patients may require a different starting dose or titration. Amantadine can accumulate in the body, so lower or less frequent dosing is needed in patients with decreased kidney function.

Therefore, patients should not increase, decrease or repeat a dose without medical advice.

Side effects of Symmetrel 100mg

As with all prescription drugs, Symmetrel may cause side effects. Common or clinically significant adverse reactions include:

• Upset stomach or nausea
• •Dry mouth (xerostomia)
• Dizziness or feeling faint
• Constipation 8
• Trouble sleeping
• Altered mental status or confusion
• Blurred vision
• Swelling in your legs or feet

Serious reactions can occur. The official label warns of serious central nervous system effects, toxicity due to overdose, vision changes due to corneal oedema and problems with abrupt withdrawal.

Important Cautions

In patients with kidney disease special care must be taken, since the body eliminates amantadine mainly via the urine. Older adults may also need their dosage adjusted.

Also, patients should inform their doctor of any seizures, heart failure, swelling, glaucoma, liver problems, psychiatric conditions and all other medications they take. Amantadine may interact with medicines that affect the nervous system or that have anticholinergic effects.

Patients should also be warned that suddenly stopping long-term treatment with amantadine can have serious neurological effects and they should not stop this medication unless they have been instructed to do so by their doctor.

Concluding Thoughts

Symmetrel 100mg is a medicine of amantadine hydrochloride, mainly used for some Parkinsonian disorders and drug-induced extrapyramidal symptoms. It also has activity against influenza A virus but the development of resistance may limit its efficacy. The medicine can have serious side effects and may need to be adjusted in some patients so proper medical supervision is important.