What randomized trials exist testing electrolyte or oral salt interventions for acute migraine relief?
Executive summary
Randomized trials directly testing oral salt or electrolyte “salt-loading” for immediate, acute migraine relief are essentially absent; the randomized evidence instead clusters around (a) intravenous magnesium for acute attacks, (b) trials of IV normal saline added to emergency care that show little benefit, and (c) large randomized dietary-sodium trials that address headache frequency over months rather than acute abortive effects [1] [2] [3] [4] [5].
1. Intravenous magnesium — the clearest randomized signal for an electrolyte intervention in acute migraine
Multiple randomized controlled trials of intravenous magnesium sulphate and other IV magnesium formulations have been performed in emergency and acute-care settings and pooled in systematic reviews and meta-analyses showing that IV magnesium can significantly relieve acute migraine within 15–45 minutes and at later timepoints (120 minutes and 24 hours) in pooled data [1] [2] [6]. Those meta-analyses drew on several small RCTs (totaling a few hundred participants across trials) and conclude IV magnesium has measurable acute effects, although individual trial methods and sizes vary and reviewers note limitations in randomization and heterogeneity [1] [2].
2. Intravenous normal saline / hydration — randomized trials show no consistent acute benefit
Randomized trials adding IV normal saline (large-volume hydration) to standard ED migraine therapy do exist and have not shown convincing, clinically meaningful improvements in acute headache outcomes: a double-blind RCT in an academic ED comparing 1,000 mL IV saline to a minimal-volume control added to NSAID therapy failed to demonstrate statistically and clinically important improvement in pain, nausea, or disability [3]. Older pooled reviews of multiple IV-fluid trials also concluded no sustained benefit from routine IV fluids for migraine in ED populations [7]. These randomized data argue against routine IV hydration as a migraine-specific abortive therapy unless clinical dehydration is present.
3. Oral salt / oral rehydration — randomized evidence is lacking for acute abortive use
There are no randomized trials identified testing oral salt-loading or branded oral electrolyte products (for example, consumer “hydration” mixes) as standalone acute migraine abortive treatments; commercial product claims lack RCT backing in migraine [8]. Discussions and reviews that catalog electrolyte strategies note oral rehydration salts as a concept and list trials assessing longer-term dietary sodium effects on headache frequency, but these address prevention or population-level headache incidence rather than immediate attack relief [9] [4].
4. Dietary sodium trials and salt substitution RCTs — impact on headache frequency, not acute attacks
Large randomized or cluster-randomized trials focused on dietary sodium—such as DASH-sodium studies and the SSaSS salt-substitution cluster RCT—have produced evidence that reducing sodium intake is associated with lower odds of headaches over time and that salt substitution can affect headache frequency/severity at the population level, but these are prevention/epidemiologic endpoints rather than evidence for acute oral salt therapy at migraine onset [4] [5] [10]. Such trials are often large and well-powered but answer a different clinical question than “can I take salt now to stop a migraine?”
5. How to interpret the gap — plausible physiology, mixed evidence, and commercial incentives
Physiologic rationales (electrolyte shifts, dehydration, magnesium deficiency) motivate research into electrolytes for migraine, and IV magnesium’s randomized signal provides biological plausibility for certain electrolytes in acute care [2] [1]. However, trials of IV saline and reviews caution that routine fluids do not equal specific migraine therapy [3] [7], and consumer-facing narratives promoting oral salt-loading or electrolyte drinks for immediate relief lack randomized-trial support and may be driven by marketing incentives rather than evidence [11] [8]. The available randomized evidence therefore supports IV magnesium in acute settings, does not support routine IV saline for non-dehydrated patients, and leaves oral salt or commercial electrolyte products unproven for aborting acute migraine.