Development and validation of a liquid chromatography-tandem mass spectrometric assay for quantitative analyses of triptans in hair

A novel method for the simultaneous determination of drugs of abuse, ethyl glucuronide and synthetic opioids in human hair through a single digestion, purification and analysis in LC-MS/MS

Polydrug use is a serious health and social problem worldwide. Over the past several years, there has been an increasing tendency to combine narcotics, alcohol, sedatives, and/or stimulants. To the traditional drugs of abuse and alcohol, an increase of new abuse drugs such as synthetic opioids has been added. In the current study, the development and validation of an innovative and fast analytical procedure has been presented to determine drugs of abuse, ethyl glucuronide and synthetics opioids in 30 mg of human hair through a single digestion, purification and analysis in LC-MS/MS. A combine simple preparation of hair sample followed to a single chromatographic run of 10 min has been proposed. A full validation for 54 target analytes for the parameters of selectivity, linearity, limit of detection, limit of quantification, accuracy, precision, matrix effects, recovery, and dilution integrity was successful completed. The method was linear in different ranges with r values of at least 0.990; the value to the validated LLOQ values were in the range 0.1-100 pg/mg. The method offered satisfactory precisions (CV<15 % and accuracy ± 20 %). In conclusion, a significant reduction in the overall times of the analytical procedure and the reduction of consumables costs make this method extremely advantageous and undoubtedly useful in routine laboratory workflow analyses and open the way to the prospect of a further implementation which also includes other classes of xenobiotics.

QuEChERS-assisted ion pair chromatography/fluorescence detection method for determination of antimigraine combination therapy in rabbit plasma samples: Application to a pharmacokinetic study

Antimigraine combination therapy has shown significant effectiveness in relieving pain, as well as reducing the frequency, duration, and severity of migraine attacks if compared to a single migraine medication. This work represents the first analytical investigation for emphasizing the synergistic effect of combining ophthalmic beta blockers with triptans in migraine treatment. The presented study was conducted to investigate the pharmacokinetic profile of almotriptan (ALM), a serotonin (5-HT1B/1D) receptor agonist used to treat migraine, when coadministered with timolol (TIM) or verapamil (VER) which are considered as an adjuvant therapy in migraine prevention. Ion pair chromatography (IPC) with online fluorescence detection was applied to simultaneously detect and quantify the binary mixtures of ALM/TIM and ALM/VER in rabbit plasma samples. The separation was achieved using a Platinum C18 analytical column with a mobile phase composed of methanol: 35 mmol L-1 phosphate buffer solution containing 10 mmol L-1 SDS at pH = 6.8 (60:40 v/v). Several parameters were evaluated during the optimization of separation conditions including mobile phase composition, buffer concentration, buffer pH and concentration of ion pair reagent. A thorough investigation of the retention mechanism was performed, and the results showed that Coulomb forces were the main contributors to the overall retention mechanism, which may be hydrophobically assisted. QuEChERS extraction technique was utilized to extract the investigated drugs from plasma samples and a detailed study was carried out to optimize partition/extraction solvents, pH, extraction salts, sample volume and clean-up step. The method had a limit of detection and quantitation of 5.6 and 16.9 ng mL-1 for ALM in ALM/TIM mixture and 2.5 and 7.6 ng mL-1 for ALM in ALM/VER mixture, with an overall recovery not less than 95.22%. This newly proposed method offers a faster alternative to existing chromatographic methods for extraction and determination of ALM in binary mixtures with TIM or VER in rabbit plasma and provides a platform for studying pharmacokinetic parameters. The coadministration of either TIM or VER with ALM resulted in a notable rise in Cmax (maximum plasma concentration) and AUC (area under the plasma concentration-time curve) of ALM, implying possible alterations in the absorption and overall exposure of ALM.

Two Spectroscopic Methods for Estimation of Anti-migraine Medications; Sumatriptan and Zolmitriptan Based on Nucleophilic Substitution Reaction

Sensitive and selective spectrophotometric and spectrofluorimetric methods have been developed for estimation of two antimigraine drugs namely sumatriptan succinate and zolmitriptan. These methods depend on producing a yellow-colored product after the reaction of the two drugs with 7-chloro-4-nitrobenz-2-oxa-1,3-diazole (NBD-Cl). The reaction products exhibit maximum absorbance at 481 nm in borate buffer of pH 9 and fluorescence emission peak at 540 nm after excitation at 470 nm for the two drugs. The linear ranges were 5-60 μg/mL for SUM and 5-50 μg/mL for ZOL in the spectrophotometric method (method I), while 0.4-4 μg/mL for SUM and 0.5-5 μg/mL for ZOL in the spectrofluorimetric method (method II). The methods validity was assessed according to ICH guidelines. Statistical analysis of the results obtained from the proposed and comparison methods confirmed that the proposed methods are highly accurate and precise. The suggested methods could be used for the determination of the mentioned drugs in both pure and tablets.

Application of Factorial and Doehlert Designs for the Optimization of the Simultaneous Separation and Determination of Antimigraine Drugs in Pharmaceutical Formulations by RP-HPLC-UV

A sensitive, precise, accurate, and specific isocratic reversed-phase high-performance liquid chromatographic (RP-HPLC) method for the simultaneous separation and determination of zolmitriptan, naratriptan, dihydroergotamine, ketotifen, and pizotifen in pharmaceutical formulations has been developed and validated. An experimental design was applied for the optimization of the chromatographic parameters. A two-level full factorial 2^k was used for studying the interaction between the variables to be optimized: the percentage of acetonitrile in the mobile phase, mobile-phase pH, nature of the buffer, and column oven temperature. The most significant parameters are the percentage of acetonitrile and the mobile-phase pH. These significant parameters were optimized using the Doehlert matrix. The optimum separation was achieved by means of a Waters XBridge C18 column (250 mm × 4.6 mm, 5 μm) with a mobile phase consisting of acetonitrile and a 10 mM sodium perchlorate buffer (38 : 62, v/v) at a flow rate of 1.0 mL·min⁻¹ and UV detection at 220 nm. The selectivity, method linearity, accuracy, and precision were examined as part of the method validation. The described method shows excellent linearity over a range of 30 to 70 μg·mL⁻¹ for all compounds with correlation coefficients higher than 0.995. The standard deviations of the intraday and interday precision were between 0.75 and 1.94%. The validated method was successfully applied to perform routine analysis of these compounds in different pharmaceutical products such as syrups and tablets. In the presence of some preservatives, it was found that there were no peaks at the related peak locations.

Polypharmacy Among Headache Patients: A Cross-Sectional Study

BACKGROUND

Polypharmacy can appropriately treat multiple chronic conditions, but it can also increase potential harm. Polypharmacy information for primary headaches is minimal, despite drugs being the main tools to manage headaches.

OBJECTIVE

The aim was to evaluate the prevalence, characteristics and risk factors of polypharmacy in patients with primary headaches and examine whether these variables differ between episodic and chronic headache patients.

METHODS

We analysed polypharmacy (simultaneous use of five or more medications), medication type, comorbidity, and risk factors in 300 patients (mean age 42.81 ± 13.21 years) with primary headaches, divided into episodic and chronic, afferent to a headache centre.

RESULTS

Patients took an average of 4.37 medications. Polypharmacy was common in 40.7% of patients, and among chronic patients, it reached 58.8%. Most patients used medications (mainly nonsteroidal anti-inflammatory drugs; 73.5%) to treat acute headaches, and 30.4% of episodic and 64.7% of chronic sufferers underwent prophylactic treatment (P < 0.0001), mostly using antidepressants (77.3%). Up to 76.7% of the cohort was taking other medications, primarily for acid-related disorders (21.7%). Comorbidities were present in 59.7% of the cohort. Variables significantly associated with polypharmacy were comorbidities, prophylactic treatment, and triptans (P < 0.001).

CONCLUSIONS

Patients with primary headaches, mainly young adults, are exposed to high polypharmacy, comparable to that of the elderly. Because increased numbers of drugs increase the risk of adverse reactions, the many medications concomitantly taken by primary headache sufferers should be frequently reviewed.

Hair analysis for detection of triptans occasionally used or overused by migraine patients-a pilot study

Purpose

The aim of this study is to evaluate the detection rate of almotriptan, eletriptan, frovatriptan, sumatriptan, rizatriptan, and zolmitriptan in the hair of migraineurs taking these drugs; the degree of agreement between type of self-reported triptan and triptan found in hair; if the concentrations in hair were related to the reported cumulative doses of triptans; and whether hair analysis was able to distinguish occasional use from the overuse of these drugs.

Methods

Out of 300 headache patients consecutively enrolled, we included 147 migraine patients who reported to have taken at least one dose of one triptan in the previous 3 months; 51 % of the patients overused triptans. A detailed pharmacological history and a sample of hair were collected for each patient. Hair samples were analyzed by liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS) by a method that we developed.

Results

All the triptans could be detected in the hair of the patients. The agreement between type of self-reported triptan and type of triptan found in hair was from fair to good for frovatriptan and zolmitriptan and excellent for almotriptan, eletriptan, sumatriptan, and rizatriptan (P < 0.01, Cohen’s kappa). The correlation between the reported quantities of triptan and hair concentrations was statistically significant for almotriptan, eletriptan, rizatriptan, and sumatriptan (P < 0.01, Spearman’s rank correlation coefficient). The accuracy of hair analysis in distinguishing occasionally users from overusers was high for almotriptan (ROC AUC = 0.9092), eletriptan (ROC AUC = 0.8721), rizatriptan (ROC AUC = 0.9724), and sumatriptan (ROC AUC = 0.9583).

Conclusions

Hair analysis can be a valuable system to discriminate occasional use from triptan overuse.

Electronic supplementary material

The online version of this article (doi:10.1007/s00228-016-2074-5) contains supplementary material, which is available to authorized users.