Rare but critical · Free checker · By an anesthesiologist
"It took hours to wake up" — scoline apnea, explained
If you — or a blood relative — once stayed paralyzed or on a ventilator long after a routine operation, it may be an inherited enzyme deficiency your anesthesiologist absolutely wants to know about. Check the pattern below and get the exact words to say.
Quick answer
Scoline apnea (suxamethonium apnea, pseudocholinesterase deficiency) is an inherited condition where two specific muscle-relaxant drugs — suxamethonium/succinylcholine and mivacurium — last hours instead of minutes, so you stay paralyzed and need a ventilator until they wear off. It's not an allergy, recovery is complete, and it's easily avoided: if your team knows, they simply use different drugs. It runs in families and can be confirmed with a blood test (dibucaine number). Tell every anesthetist, every time.
Does this story fit? Tick anything that's true for you or a blood relative:
What actually happens — and why it ends well when the team knows
During some anesthetics the team uses a fast, short-acting muscle relaxant — suxamethonium — that normally wears off within minutes because an enzyme in your blood destroys it. Roughly 1 in 2,000–3,000 people inherit a version of that enzyme that works slowly or barely at all. In them the drug keeps working for hours. The person is completely safe as long as the anesthetic is simply continued: kept asleep, kept on the ventilator, muscles monitored, and woken only when strength has fully returned. There is no organ damage and no lasting harm.
Once it has happened once, it should never surprise anyone again: future anesthetists just pick from the many alternative muscle relaxants that don't rely on that enzyme. That's why the single most valuable thing you can do is say the story out loud at every pre-op visit — even a vague version of it.
If the story fits: your 3-step plan
- 1. Tell every anesthetist, every time — use the script from the checker above. Also add it to our printable disclosure card.
- 2. Ask for the blood test — pseudocholinesterase activity + dibucaine number confirms it for you and unlocks testing for your children, siblings and parents.
- 3. Get it in writing — a letter or alert card in your records, and consider a medical-alert bracelet if confirmed.
Frequently asked questions
What is scoline apnea (suxamethonium apnea)?
Some people are born with low or unusual levels of an enzyme (pseudocholinesterase, also called butyrylcholinesterase) that normally breaks down two specific anesthetic muscle-relaxant drugs — suxamethonium (succinylcholine, 'scoline') and mivacurium. In most people these drugs wear off in minutes. In affected people they can last for hours, so the muscles — including breathing muscles — stay paralyzed long after the operation is over. It is not an allergy and not brain damage: the person simply needs to be kept asleep and breathing on a ventilator until the drug wears off, and then wakes up normally.
Is scoline apnea dangerous?
Only if the team doesn't expect it. When it happens, the anesthesiologist keeps you safely sedated and ventilated until muscle strength returns — recovery is complete. The real danger is being awake but paralyzed if the team assumes the drug has worn off, which is why telling every future anesthetist is so important. If they know in advance, they simply avoid those two drugs entirely — plenty of alternatives exist.
Does scoline apnea run in families?
Yes — it's inherited. If a parent, sibling or child had a confirmed episode ('took hours to wake up', 'stayed on the ventilator after a routine op'), you may carry the same gene. A blood test (pseudocholinesterase activity and the dibucaine number) can confirm it. Tell your anesthesiologist about the family story even if you've never been tested — they'll avoid the trigger drugs as a precaution.
How do I get tested for pseudocholinesterase deficiency?
Ask your doctor for a pseudocholinesterase (butyrylcholinesterase) activity test with a dibucaine number — a simple blood test. If it confirms the deficiency, ask for a written letter or alert card, consider a medical-alert bracelet, and make sure the result is in your hospital record. First-degree relatives can then be tested too.
Is scoline apnea the same as malignant hyperthermia?
No — they're different inherited conditions that both surface under anesthesia. Malignant hyperthermia is a dangerous runaway rise in temperature and muscle breakdown triggered by certain anesthetic gases and suxamethonium. Scoline apnea is prolonged paralysis only, managed by waiting safely on a ventilator. Both deserve a clear mention to your team; if the family story is vague ('a relative had a bad reaction'), see our family-history guide and let the anesthetist work out which it was.