What Are Autonomic Dysreflexia Symptoms After SCI?

Autonomic dysreflexia (AD) is a medical emergency characterized by a sudden, dangerous spike in systolic blood pressure—typically 20 mmHg or more above your usual resting baseline ^[1][2]. It primarily affects people with spinal cord injuries at or above the T6 level, though it can occasionally occur in those with lower injuries ^[3][1]. Because individuals with spinal cord injuries often have a lower baseline blood pressure, a reading that looks “normal” for someone else might be dangerously high for you ^[2]. This reflex is your body’s uncontrolled reaction to an irritating stimulus occurring below your level of injury, even if you cannot physically feel it ^[3]. Left untreated, it can lead to serious complications such as seizures, stroke, brain hemorrhage, heart failure, and even death ^[4][5].

Symptoms: What Autonomic Dysreflexia Feels Like

Symptoms can be absent or atypical. While some episodes present with distinct warning signs, many people experience silent autonomic dysreflexia, where their blood pressure spikes to dangerous levels without any obvious physical symptoms at all ^[5][2]. If you have a known trigger or feel unwell, always check your blood pressure.

When symptoms do occur, they may include:

• A sudden, severe, or pounding headache ^[5]
• Heavy sweating or flushing of the skin above your level of injury ^[5]
• Goosebumps above or below the level of injury
• Blurred vision or visual changes ^[5]
• Nausea or a sudden feeling of anxiety ^[5]
• Changes in heart rate (often a slower heart rate, but a fast pulse can also occur) ^[3][5]

Common Triggers

AD is triggered by an irritant below your injury level that your nervous system cannot properly process due to the spinal cord damage ^[3].

The most common triggers include:

• Bladder issues: A full or distended bladder is the leading cause of AD. This can happen due to a blocked, kinked, or overfilled catheter, a missed catheterization, or a urinary tract infection ^[6][7]. Medical procedures involving the bladder can also trigger an episode ^[8].
• Bowel issues: Constipation, fecal impaction, or a distended bowel are also major triggers. Routine bowel care programs or sensory stimulation can sometimes trigger a response ^[9][10].
• Skin issues: Pressure injuries (bedsores), ingrown toenails, burns, or even wearing clothing, belts, or shoes that are too tight ^[11][12].
• Other triggers: Fractures, menstruation, sexual stimulation, or infections anywhere below the injury level ^[13][14].

Immediate Action Steps: What to Do

If this is happening now, this is a medical emergency. Follow these steps and have a caregiver help if possible:

1. Sit up and lower your legs: If you are lying down, sit up immediately and lower your legs if safe to do so. This uses gravity to help naturally lower your blood pressure ^[15][16].
2. Loosen restrictive items: Immediately remove or loosen any tight clothing, abdominal binders, compression stockings, belts, or shoes ^[15][16].
3. Check your blood pressure frequently: Compare it against your usual resting baseline ^[17][15]. Continue checking it regularly while you look for the trigger.
4. Find and remove the trigger (Start with the bladder):
   • If you use a catheter, check the tubing for kinks, closed clamps, dependent loops, or an overfull drainage bag ^[5][6].
   • Do not force catheter irrigation. Only perform intermittent catheterization or replace a catheter if you are trained and it is part of your specific care plan ^[5][6]. If the catheter is blocked and you cannot safely restore drainage, seek urgent medical help ^[5][6].

What NOT to Do During an Episode

• Do not lie flat. Lying down can further increase your blood pressure ^[15].
• Do not perform an unplanned bowel check. While bowel impaction is a common trigger, do not attempt unplanned digital stimulation, rectal examinations, or disimpaction while your blood pressure is high, as this can severely worsen the episode ^[9][10]. Bowel checks should only be done following a clinician-provided protocol (often using a prescribed topical anesthetic) and must stop if blood pressure worsens ^[9].
• Do not wait for symptoms. Do not wait for severe symptoms like chest pain or confusion before seeking help ^[15].
• Do not use unprescribed medications. Never use someone else’s blood pressure medication or take an unprescribed dose ^[15].

When to Call for Emergency Help

Call emergency services immediately if:

• Your blood pressure remains 20 mmHg (or your personalized threshold) above your baseline and does not improve ^[15][18].
• You cannot quickly find or safely remove the trigger (such as a failed catheterization) ^[15][18].
• You experience red-flag symptoms such as severe or persistent headache, difficulty breathing, seizures, loss of consciousness, or symptoms of a stroke ^[15][18][4].

Emergency Medications

If your doctor has prescribed a fast-acting rescue vasodilator (blood pressure medication), use it only strictly according to your individualized plan and under clinician guidance ^[15][16]. Be aware that blood pressure can drop dangerously low (hypotension) after the trigger is removed, so careful monitoring is required ^[1][19]. Always consult your doctor beforehand about potential interactions, especially if you take other medications.