Aminophylline Injection Alleviates Pain in Postdural Puncture Headache

Aminophylline in pain and migraine

Although the pathogenesis of migraine is not fully understood, accumulating evidence indicates migraine may be driven by impaired brain energy metabolism in the context of pathologically high levels of adenosine. Considerable evidence indicates that aminophylline, an adenosine receptor antagonist, can provide strong therapeutic relief in pain, particularly post-dural headache. Moreover, direct observations from a previously published observational case series have demonstrated a strong therapeutic impact of low-dose aminophylline in patients with severe, unremitting migraine attacks. Although higher doses of aminophylline are associated with an unfavourable adverse effect profile, low doses of aminophylline are associated with minimal adverse effects. Despite this promise, double-blinded randomized trials will be needed to determine the true therapeutic efficacy of low-dose aminophylline in migraine.

Aminophylline for treatment of postdural puncture headache: A randomized clinical trial

OBJECTIVE

To investigate the efficacy and safety of IV aminophylline for patients with postdural puncture headache (PDPH).

METHODS

We randomly assigned patients to groups receiving either 250 mg IV aminophylline or a placebo within 3 hours of symptom onset once daily for 2 consecutive days. The primary endpoint was headache severity 8 hours after treatment. We assessed this using visual analog scale (VAS) scores taken from patients in a standing position. We also recorded posttreatment VAS score changes, Patient Global Impression of Change (PGIC) scores, and adverse events. We performed an intention-to-treat analysis.

RESULTS

We enrolled 126 patients with PDPH at 5 centers in China (62 assigned to the aminophylline group and 64 to the placebo group). The median age was 37 years, and 96 (76.2%) patients were women. Compared to the placebo-treated patients, the aminophylline-treated patients had significantly lower mean VAS scores 8 hours after treatment (5.34 vs 2.98, p < 0.001) and were significantly more likely to report improvements on the PGIC (39.1% vs 72.6%, p < 0.01). This therapeutic effect was already evident at the 30-minute time point and persisted for 2 days. There was no significant difference in the incidence of adverse events (4.8% vs 1.6%, p = 0.589).

CONCLUSIONS

IV aminophylline is an effective and safe early-stage treatment for patients with PDPH.

CLINICALTRIALSGOV IDENTIFIER

NCT02522013.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that for people with PDPH, IV aminophylline reduces headache severity.