I fact checked all of these using Snopes.com and Wikipedia and they seem to be accurate.
The platypus is one of the few living mammals to produce venom. The venom is made in venom glands that are connected to hollow spurs on their hind legs; it is primarily made during the mating season. While the venom’s effects are described as extremely painful, it is not lethal to humans.
The different chemicals in the venom have a range of effects from lowering blood pressure to causing pain and increasing blood flow around the wound. Coagulating effects have been seen during experiments on laboratory animals, but this has not been observed consistently. Unlike snake venom, there appears to be no necrotising component in the platypus’s venom. While some muscle wastage has been observed in cases of envenomation in humans, it is likely due to the inability to use the limb while the effects of the venom persist. It is unknown whether the pain caused is a result of the associated edema around the wound or the venom has a component that acts directly on the pain receptors.
Although powerful enough to paralyse smaller animals, the venom is not lethal to humans. Yet, it produces excruciating pain that may be intense enough to incapacitate a victim. Swelling rapidly develops around the entry wound and gradually spreads outward. Information obtained from case studies shows that the pain develops into a long-lasting hyperalgesia that can persist for months but usually lasts from a few days to a few weeks. A clinical report from 1992 showed that the severe pain was persistent and did not respond to morphine.
In 1991 Keith Payne, a former member of the Australian Army and recipient of the Victoria Cross (Australia’s highest award for valour), was struck on the hand by a platypus spur while trying to rescue the stranded animal. He described the pain as worse than being struck by shrapnel. A month later he was still experiencing pain in that hand. In 2006, Payne reported discomfort and stiffness when carrying out some physical activities such as using a hammer. Wikipedia.