Objectives: The cost-effectiveness of available pharmacological treatments for narcolepsy is largely unknown. Available pharmacological treatments are associated with tolerability, abuse, and adherence issues. Pitolisant is the first inverse agonist of the histamine H3 receptor to be prescribed for the treatment of narcolepsy with and without cataplexy. Studies suggest that pitolisant is both as effective as previously introduced drugs and is associated with fewer adverse effects. The objective in this study was to estimate the cost-effectiveness of pitolisant as monotherapy, and pitolisant as an adjunctive treatment to modafinil, compared with standard treatment. Materials & Methods: Calculations were performed using a Markov model with a 50-year time horizon. Healthcare utilization and quality-adjusted life years (QALYs) for each treatment alternative were calculated assuming no treatment effect on survival. Probabilistic sensitivity analyses were performed for treatment effectiveness and healthcare cost parameters. Results: The cost per additional quality-adjusted life year was estimated at SEK 356 337 (10 SEK ≈ 1 Euro) for pitolisant monotherapy, and at SEK 491 128 for pitolisant as an adjunctive treatment, as compared to standard treatment. The cost-effectiveness measure was demonstrated to be particularly sensitive to the assumptions made concerning indirect effects on total healthcare utilization and the pitolisant treatment cost. Conclusions: The incremental cost-effectiveness ratios were below the unofficial willingness-to-pay threshold at SEK 500 000. The estimated costs per additional QALY obtained here are likely to overestimate the true cost-effectiveness ratio since significant potential indirect effects—pertaining both to labor-market and household-related productivity—of treatment are not taken into account.