Norflex contains orphenadrine citrate 100 mg, a muscle relaxant. It is used for painful muscle spasm — back and neck spasm, and spasm after injury — and in South Africa it is also registered for Parkinsonism and drug-induced movement effects. Norflex Co additionally contains paracetamol. It causes drowsiness and dry mouth.
What is Norflex?
Norflex contains orphenadrine citrate 100 mg. A second product, Norflex Co, contains orphenadrine citrate 35 mg together with paracetamol 450 mg — check which you have, because it changes what else you can safely take.
Orphenadrine is a muscle relaxant with antimuscarinic and antihistamine properties. It works centrally, in the brain and spinal cord, reducing the nerve activity that drives muscle spasm — rather than acting on the muscle fibre directly. It also reduces the activity of acetylcholine, a signalling chemical, which is the basis of its second use.
That gives it two quite different registered roles in South Africa:
Painful muscle spasm, where it relaxes the protective spasm that develops around an injured or strained area and often prolongs the pain.
Parkinsonism and extrapyramidal effects. In Parkinson’s disease, dopamine falls while acetylcholine activity becomes relatively excessive. Reducing acetylcholine helps rebalance that, particularly for tremor and rigidity. It is also used for the movement side effects some antipsychotic medicines cause.
It is a Schedule 3 medicine, supplied here by Inova Pharma.
What is Norflex commonly used for?
Norflex is prescribed for:
- Acute painful muscle spasm — lower back spasm, neck spasm, spasm after a strain or injury.
- Muscle spasm accompanying musculoskeletal conditions, where the spasm itself is worsening the pain.
- Generalised pain with a muscular component, particularly as Norflex Co with paracetamol.
- Parkinsonism, for tremor and rigidity.
- Extrapyramidal effects caused by antipsychotic medicines.
The muscle spasm use is what drives most searches. Spasm is worth understanding: when you injure your back, surrounding muscles tighten protectively. That guarding is useful briefly and then becomes part of the problem — tight muscle hurts, restricts movement, and slows recovery. A muscle relaxant breaks that cycle enough to let you move.
Which points to something important: movement is the treatment for most back pain. Current guidance is to stay as active as the pain allows rather than resting in bed, which prolongs recovery. Norflex is there to make that possible, not to replace it.
It is intended for short-term use in muscle spasm.
How Norflex fits into this medicine category
Norflex is a muscle relaxant, a group that works differently from the painkillers around it:
| Group | Examples | What it does |
|---|---|---|
| Muscle relaxants | Orphenadrine (Norflex), methocarbamol | Reduces the nerve drive causing spasm |
| Simple analgesics | Paracetamol | Relieves pain |
| Anti-inflammatories | Diclofenac, ibuprofen, etoricoxib | Reduces inflammation and pain |
| Corticosteroids | Prednisone | Suppresses inflammation, as courses |
| Opioids | Tramadol, codeine | Moderate to severe pain |
For back spasm, a muscle relaxant is often combined with a painkiller or anti-inflammatory, because they address different parts of the problem. That is the reasoning behind Norflex Co. See the pain, inflammation and musculoskeletal medicines hub.
What to check before using Norflex
Check whether you have Norflex or Norflex Co. If it is the combination, it contains paracetamol — do not take a separate paracetamol product alongside it.
Do not drive until you know how it affects you. Drowsiness is common.
Tell your prescriber or pharmacist if:
- You have glaucoma, particularly narrow-angle. Antimuscarinics can raise pressure in the eye.
- You have an enlarged prostate or difficulty passing urine.
- You have myasthenia gravis.
- You have a heart condition, especially a fast or irregular heartbeat.
- You have a bowel obstruction or significant constipation.
- You are pregnant or breastfeeding.
- You are older. Antimuscarinic medicines are associated with confusion and falls in older adults, and are used with more caution.
- You take other antimuscarinic medicines — some antidepressants, antihistamines, bladder medicines. The effects add up.
- You take other sedating medicines, or drink alcohol.
Follow the dispensing label. This page does not set doses.
Possible cautions and when to ask a pharmacist or doctor
Expect dry mouth and drowsiness. These are the commonest effects. Blurred vision, constipation and difficulty passing urine also occur.
Confusion in older adults is a recognised risk with this class. Report new confusion, agitation or unsteadiness, particularly in someone elderly — it may be the medicine rather than anything else.
Alcohol adds to the sedation.
Short-term use for spasm. If muscle spasm is not settling within a week or two, the answer is usually assessment and physical treatment rather than continuing the tablets.
Keep moving. For back pain, gentle activity within the limits of the pain speeds recovery. Prolonged rest does not.
Do not stop Parkinson’s treatment abruptly if you take it for that purpose — speak to your prescriber.
Seek medical attention for eye pain with blurred vision or halos around lights, inability to pass urine, palpitations or an irregular heartbeat, confusion, or a rash with swelling. See a doctor promptly for back pain with numbness in the groin or inner thighs, loss of bladder or bowel control, or leg weakness — those need urgent assessment and are not muscle spasm.
Related medicine guides
- Browse Pain, Inflammation & Musculoskeletal Medicines guides
- Read: Prednisone used for
- Read: Donapan used for
Frequently asked questions
What is Norflex used for? Painful muscle spasm — back and neck spasm, and spasm after injury. In South Africa it is also registered for Parkinsonism and for movement side effects of antipsychotic medicines.
What is the difference between Norflex and Norflex Co? Norflex contains orphenadrine 100 mg. Norflex Co contains orphenadrine 35 mg plus paracetamol 450 mg. Do not add separate paracetamol to the combination.
Is it a painkiller? Not directly. It relaxes muscle spasm, and pain caused by that spasm eases as a result. It is often taken alongside a painkiller.
Will it make me drowsy? Commonly, yes. Do not drive until you know how it affects you, and avoid alcohol.
Why is it also used for Parkinson’s? It reduces acetylcholine activity, which helps rebalance the acetylcholine-dopamine relationship disturbed in Parkinsonism, particularly for tremor and rigidity.
How long should I take it for muscle spasm? Short-term. If spasm is not settling within a week or two, ask for assessment rather than continuing.