| Drug Name | pH range | Known iv reactions | Number of reports to extravasation.org.uk |
| Ranitidine (hydrochloride) | 6.7 - 7.3 | | 0 |
| Remifentanil (hydrochloride) | 2.5 - 3.5 | | 0 |
| Rifampicin | 8.0 - 8.8 | Venous thrombosis | 0 |
| Ritodrine (hydrochloride) | 4.8 - 5.5 | | 0 |
| Rocuronium | 3.5 - 4.0 | | |
| Ropivacaine (hydrochloride) | | Pain on injection, pruritis | 0 |
| S/C only not IV | | | 0 |
| Salbutamol | | | 0 |
| Secretin | 2.5 - 5.0 | | |
| Sodium bicarbonate 4.2% and 8.4% | 7.0 - 8.5 | Extravasation may cause tissue necrosis, skin sloughing, and ulceration or chemical cellulitis. | 7 |
| Sodium calciumdetate | 6.5 - 8.0 | | 0 |
| Sodium chloride 0.9% | 4.5 - 7.0 | Thrombophletis, bruising of vein. | 7 |
| Sodium fusidate | 7.4 - 7.6 | | |
| Sodium lactate | 6.0- 7.3 | | 0 |
| Sodium nitroprusside | 3.5 - 6.0 | | 0 |
| Sodium stibogluconate | 5.6 | Venous thrombosis, pain at injection site, erythema, pruritis. IM injection may be associated to abscess formation. | 0 |
| Sodium tetradecyl sulphate | | Erythematous rash develops 30-90 mins post injection, local tissue necrosis, pain at injection site, urticaria or ulceration may also occur | 0 |
| Sodium valproate | 6.8 - 8.5 | | 0 |
| Soluble insulin | | | 0 |
| Somatropin | | Local urticarial reactions are rare | 0 |