Medications for Spinal Stenosis

Commonly Used Medications

1. Anti-Inflammatory Pain Relievers (NSAIDs and Acetaminophen) — For Inflammatory Pain

These are effective for nociceptive pain (inflammatory pain). However, they tend to be less effective for neuropathic pain (tingling, burning, or electric-shock-like sensations).

Guideline recommendation (Evidence B): NSAIDs are suggested for patients with the nerve root type or those who also have back pain, for short-term use. For patients with the cauda equina type, NSAIDs are not considered beneficial — limaprost (a blood flow enhancer) has been shown to be more effective at improving numbness, walking distance, and quality of life.

2. Gabapentinoids — For Nerve Pain with Numbness

How they work: These medications act on calcium channels inside your nerve cells, reducing the abnormal signals (pain signals) that damaged nerves send out.

Important tips for taking these medications:

• Start with a low dose and increase gradually (this is called "titration")
• It may take several days to several weeks before you feel the full benefit
• The dose is adjusted based on how well your kidneys are working
• Do not stop suddenly — the dose needs to be tapered down gradually

Possible side effects and what to do about them:

A note for older patients: As we age, our kidneys may not clear medications as quickly, which means the drug stays in your body longer. For this reason, lower starting doses are used. Be especially careful about dizziness and unsteadiness, which can lead to falls. The good news is that these side effects often improve as your body adjusts to the medication.

What the guidelines say (Evidence B): The clinical guidelines state that a clear recommendation for or against gabapentinoids cannot be made, because results from four clinical trials were inconsistent. However, this does not mean they don't work. Gabapentinoids are widely recognized as effective for neuropathic pain, and your doctor will decide whether to prescribe them based on your individual symptoms.

Some patients are reluctant to increase the dose because of side effects. However, research shows that gabapentinoids generally become more effective at higher doses (dose-dependent response). By increasing gradually, side effects can be minimized. Work with your doctor to find the dose that gives you the best relief.

3. Medications That Strengthen Your Body's "Pain Brakes" — For Chronic Pain

How it works: Duloxetine boosts the activity of two chemical messengers — serotonin and norepinephrine — that your brain uses to send "turn down the pain" signals through the spinal cord. This system is called the descending pain inhibitory pathway — your body's natural pain brake.

Duloxetine was originally developed to treat depression. Later research revealed that it also reduces pain sensitivity, and it is now widely prescribed for chronic back pain, joint pain, and nerve pain.

Treatment starts with a low dose and is increased gradually based on how you feel. It often takes a few weeks before you notice the full benefit, so it's important to be patient and keep taking it as directed.

Don't be alarmed by the word "antidepressant." Duloxetine's pain-relieving effect works through a different mechanism than its antidepressant effect. In fact, the pain relief kicks in at lower doses and sooner than the mood effects. Your doctor is prescribing it for pain management, not for depression.

Possible side effects:

If you notice any unusual symptoms, don't try to tough it out — speak with your doctor.

4. Blood Flow Enhancers

How it works: This medication widens blood vessels and improves blood flow, helping to restore the blood supply to compressed nerves. It is particularly effective for intermittent claudication — the symptom where your legs go numb while walking and you need to stop and rest.

Guideline recommendation (Evidence A — the highest level of evidence for any medication in spinal stenosis): Limaprost is recommended for patients with the cauda equina type or mixed type (Strength 2, consensus rate 85%). Multiple clinical trials have confirmed improvements in leg numbness, walking distance, and quality of life (QOL). Importantly, no increase in adverse events was reported compared to other medications, making it a medication with a strong safety profile. On the other hand, evidence for its effectiveness against nerve root-type pain (strong one-sided pain) is lacking.

5. Weak Opioid Pain Relievers — For Moderate to Severe Pain

How they work: Tramadol is a stronger pain reliever used when anti-inflammatory medications are not enough. It works by acting on "pain switches" in the brain and spinal cord to weaken pain signals. It also supports your body's descending pain inhibitory pathway (the natural "pain brake" system), helping to reduce how pain is transmitted. It is used for cancer pain, chronic back and joint pain, and nerve pain.

Possible side effects: Common side effects include nausea, constipation, drowsiness, dizziness, and feeling foggy or lightheaded.

A note for older patients: In older adults, drowsiness and dizziness can increase the risk of falls, and constipation may become particularly bothersome. Be especially careful when first starting the medication or when the dose is increased. If you notice anything unusual, don't try to push through it — let your doctor know right away.

6. Other Medications

About Methylcobalamin (Vitamin B12): One clinical trial (152 patients, 24 months) showed improvement in walking distance, but because it was combined with other treatments, it is not possible to determine whether methylcobalamin alone was responsible. It should be considered supplementary at best.

About herbal medicine (Hachimijiogan): One clinical trial (27 patients, 8 weeks) showed improvement in back pain, numbness, and intermittent claudication, with no adverse events. However, the small sample size means the evidence is limited. It should also be considered supplementary.