Cave slimes have a maximum melee hit of 27 LP, and are poisonous. The poison starts at 32 LP and is inflicted in one of two ways: when they attack (whether the attack inflicts damage or not), and when they are hit with a close melee attack (even if the attack kills the slime). In either case, the player will be poisoned nearly 100% of the time, unless the player protects themselves accordingly by taking Anti-poison potions or using the thermal bath Spa at Oo'glog before fighting cave slimes. Super antipoison potions are recommended as each dose gives immunity to poison for 6 minutes. An alternative for higher levelled players is to bring decent food, such as monkfish (the money made off of swamp tar is more than the cost of the monkfish), to offset damage from the poison, as their melee attacks rarely do any direct damage, and the poison is generally mild. The best option for players with 60 Dungeoneering, 60 Defence, and 70 Herblore is to equip an Anti-poison totem, which completely eliminates the need for antidotes, but costs 44,000 Dungeoneering tokens to buy. Alternatively, players may use the Poison Purge aura, which removes the need for antipoison and food for the time it lasts.
Although these monsters have good drops, some lower levelled players do not prefer to train on them due to large number of antipoison potions required. However, players who can kill the slimes quickly can usually make a profit from the swamp tar drops, even after paying for the super antipoison potions or their ingredients.
Players using long-range combat (magic, ranged, or long melee weapons like Halberds) do not need any poison protection as long as they use Safe spots. There is a safe spot near the south-west fishing spot in Lumbridge swamp cave (see picture).
Players should not go into the Lumbridge Swamps dungeon with an open light (this includes candles, torches, etc.), as the flame will eventually cause the gases in the cave to explode. This can cause massive damage to the player (up to 200, depending on the player's constitution) and possibly death if the player's life points are low enough. Also, the light source will be extinguished, and swarming insects will then constantly hit 10s on the player until the player relights a light source, escapes the cave, or dies. An enclosed light source like a Bullseye lantern or a flameless light source like a Seers' headband 1 (or higher) will not ignite the gases and is highly recommended.
A tip for Cave Slimes would be to equip a Holy symbol use the Prayer book from The Great Brain Robberyquest, This allows you to camp at the cave slimes for a long time. However, this doesn't provide immunity, and you will likely be poisoned again right away if the slime is still alive or if you attack another slime (even if you kill the slime in one hit).
Previously, equipping an Anti-poison totem would not prevent Cave slimes and certain other poisonous monsters from causing poison. On 15 June 2010, Jagex implemented a fix that addressed the issue. However, during the fix, cave slimes were overlooked, and could still cause poison even if the player was holding the anti-poison totem. As of 21 September 2010, this glitch has been fixed (the exact date of the fix is unknown, and most likely occurred in a hidden update).