Lidocaine-prilocaine cream is the most effective medication used for IUD insertion-related pain, as reviewed in a study published in the journal 'Fertility and Sterility'.

The intrauterine devices (IUDs) are highly effective long-acting reversible contraceptives (LARC) either used in the form of levonorgestrel (LNG) or copper-bearing devices. Ahmed Samy et al. reviewed the evidence on the most effective medications for the IUD insertion-related pain relief.

The patients receiving different medications for pain relief versus those who received placebo were considered in this systematic review and network meta-analysis of the randomized controlled trials.

The electronic database search included the bibliographic databases, i.e., SCOPUS, Medline via PubMed, ScienceDirect, Web of Science and Cochrane Central Register of Controlled Trials (CENTRAL). The primary outcome measures comprised of the Visual analog scale (VAS) pain score during tenaculum placement, IUD insertion, and 5 - 20 minutes after insertion, the score of easiness of insertion and need for additional analgesics.

Thirty-eight RCTs containing 6,314 patients were included in the present review. The network meta-analysis depicted statistically significant reduction at tenaculum placement with lidocaine-prilocaine cream (genital mucosal application) compared to placebo. It was found that lidocaine-prilocaine cream was ranked the highest in reducing the pain at tenaculum placement, and then lidocaine (paracervical) considering the ranking probability order. In the same way, lidocaine-prilocaine cream was ranked as the highest treatment in pain reduction during the IUD insertion, followed by lidocaine (paracervical).

The study authors concluded, "Other medications are not effective."