Patients' response to migraine medication does not seem to be consistent. Nausea linked to migraine is quite common, and further reduces the efficacy of oral medications. Treatment outcomes are probably affected due to the delay in taking oral medicines by the patients. Delayed gastric emptying also hinders drug absorption finally resulting in poor bioavailability of the drugs. Previous research has demonstrated that having nausea at the time of drug administration is linked to a weaker response to Triptan treatment. It will be fascinating to know the efficacy of other migraine medications in patients with a poor response to Triptans.

A post hoc sub analysis of two randomized, controlled Phase 3 trials were conducted to discover whether nausea or prior Triptan treatment of migraine affect the efficacy of Diclofenac potassium in migraine treatment or not. The study comprised 1272 patients, 644 on active drug and 628 on placebo. Out of 1272 patients, 85% were women. After collecting data, post hoc subgroup analyses were performed in patients with and without nausea at baseline, and patients with and without prior Triptan treatment. The treatment efficacy assessments involved the percentage of patients who, at 2 hours post dosing were headache pain-free, without nausea, without a severe degree of disability, without photophobia or phonophobia. Further, to evaluate the treatment effects, a Cochran-Mantel-Haenszel test was used. Effects of nausea or prior Triptan use were determined by using logistic regression with factors of treatment group and interaction of treatment group by nausea or prior Triptan use at the time of dosing, nausea or prior Triptan use at the time of dosing or analysis center.

Out of 1272 patients, prior Triptan use was noted among 570 patients, and nausea was reported among 783 patients, at the time of dosing. The patients in the active treatment group showed statistically significantly better response for headache pain, nausea, photophobia, and phonophobia than those receiving placebo, regardless of whether they had nausea at baseline. During logistic regression analysis, only treatment group anticipated response for these parameters without any group interaction. Further, both treatment group, as well as baseline nausea, assumed whether patients recorded severe disability at 2 hours or not. The active treatment group was likely to be considerably headache pain-free at 2 hours after dosing, whether or not they had previously been treated with the Triptan. However, among the active treatment group, Triptan-naïve patients showed better improvements in headache pain than Triptan-experienced patients. Also, the Triptan-naïve patients of placebo groups were more likely to be Pain-Free. According to logistic regression analysis, the treatment group assumed a headache pain response; Triptan use predicted a lack of response and no interaction was seen between the two. Further, Prior Triptan use did not predict any of the other outcome measures.

The overall results of the study confirm that nausea does not abolish the Diclofenac potassium effectiveness for oral use, at the time of dosing. Further, the rapid absorption profile may also increase the Diclofenac potassium effectiveness in patients having nausea. Those patients who predicted poorer headache response at 2 hours post dose, prior Triptan use are more likely to be refractory to both Triptans and Diclofenac.

Thence, Diclofenac potassium for oral solution is useful in Triptan-naïve patients, but no stable assumption can be made from this study regarding how to order treatment.