Grimy snake weed is a herb found by searching marshy jungle vines. It can be cleaned to obtain snake weed. It is a secondary ingredient in Herblore, as it is used with rogue's purse to make a Relicym's balm potion. It is also used as secondary ingredient to make Sanfew serum. Adding the herb to a vial of water will produce a snakeweed mixture. Cleaning the herb yields 2.5xp.
Twenty marshy jungle vines are found south-west of Tai Bwo Wannai in west Karamja, just west of the hunter area. Grimy snake weed is also a common drop from Jogres, which is very convenient for players with higher combat levels who are trying to make Relicym's Balm, as many reside in the cave where the other needed herb, Rogue's Purse, is found. It can also sometimes be found inside barrels.