Peter is surprised to find that he has lost his abilities.
Ability loss is a condition in which an evolved human is unable to use his/her ability. Ability loss can be temporary or permanent, and caused by a number of means. Known ways of causing this condition include drugs, the effects of certain evolved human abilities, the Shanti virus, or rarely through solar eclipses. An evolved human's self-confidence, or rather lack thereof, can also affect ability performance.
Most evolved humans lose the use of their abilities when near the Haitian. This ability loss only temporary, as the use of abilities returns when the Haitian leaves or is incapacitated. There have been examples of abilities being used in the Haitian's presence, such as when Nathan flew away (Hiros), or when the Haitian had to use thermal imaging goggles to see Peter and Claude who were both invisible, despite being just a few feet away from the Haitian (Unexpected), but it is unknown if it was due to the abilities not being affected by his power or the Haitian simply not exerting it in those instances.
For a full list of powers that have been blocked by the Haitian's ability, see the mental manipulation article.
Arthur Petrelli has shown that he can steal the abilities of other evolved humans, rendering them powerless. The absorption itself does not kill the victim, as is the case with Linda Tavara's ability. Arthur is known to have stolen the following powers:
- Telepathy from an unknown source and Peter Petrelli (Dying of the Light)
- Rapid cell regeneration from Adam Monroe and Peter Petrelli (Dying of the Light)
- Electric manipulation from Peter Petrelli (Dying of the Light)
- Telekinesis from Peter Petrelli (Dying of the Light)
- Poison emission from Maya Herrera (Eris Quod Sum)
- Mental manipulation from an unknown source (Villains)
- Space-time manipulation from Peter Petrelli (It's Coming) and Hiro Nakamura (Our Father)
- Precognition from Peter Petrelli (It's Coming)
According to Arthur, the effects of power absorption are permanent. He can remove an ability which he already possesses, as in the case of Peter's rapid cell regeneration and telepathy, and Hiro's space-time manipulation.
An ability stolen by Arthur can be, at first partially and later fully restored by Matt Parkman, Jr.'s ability, as seen with Hiro Nakamura. After being touched by Matt Parkman Jr., Hiro was able to access the time-stopping part of his original ability. This seems to indicate that Arthur's power to steal an ability does not damage the victim's DNA, but rather inactivates the portion of DNA in question. Hiro has also regained his ability, though it took a long time to regain full control over it due to a brain tumor he developed. Although Arthur initially said it was impossible for Peter to regain his powers, during their final confrontation, he indicated that he believed that the formula could restore them. However, when Peter did inject himself with the formula, he ended up with a different, though similar, power.
Peter Petrelli loses his currently replicated ability when he absorbs a new one. (Trust and Blood) Peter has discarded the following abilities:
- Flight from Nathan Petrelli, Sylar and West Rosen (A Clear and Present Danger, Exposed, An Invisible Thread, The Fifth Stage, Close to You, Brave New World)
- Enhanced strength from Mohinder Suresh (A Clear and Present Danger, Jump, Push, Fall)
- Freezing from Tracy Strauss (Trust and Blood)
- Telepathy from Matt Parkman (Exposed, Brave New World)
- Shape shifting from Sylar (Orientation)
- Super speed from Edgar (Hysterical Blindness)
- Enhanced synesthesia from Emma Coolidge (Tabula Rasa)
- Space-time manipulation from Hiro Nakamura (Tabula Rasa)
- Healing touch from Jeremy Greer (Brother's Keeper)
- Mental manipulation from René (Let It Bleed)
- Rapid cell regeneration from Claire Bennet (Let It Bleed)
- Precognitive dreaming from Angela Petrelli (The Art of Deception)
It is unknown if opium will still cause ability loss for evolved humans with abilities that are passive or require little concentration.
After being captured by the Company, Peter is given ability negation pills in order to suppress his powers. The effects of the pills are temporary, as they wore off after a few days of not taking them (Four Months Ago...).
With the help of the US government, Nathan developed a system to negate abilities and keep evolved humans in a stupor. Part of the system incorporates a device that administers an unknown drug intra-nasally to the evolved human.
The Shanti virus
- Molly Walker contracted the Shanti virus and was thus unable to access her ability. Mohinder cures her using his own blood and Molly fully regains her ability (The Hard Part).
- The Haitian contracted the Shanti virus at some point and was unable to access his ability. Mohinder cured him with the antibodies of his own blood, and the Haitian was able to access and use his ability shortly thereafter (Lizards).
- Sylar contracted the Shanti virus and was unable to use any of his abilities (Kindred). However, when he was cured by injecting himself with a stolen mixture of Claire Bennet and Mohinder Suresh's blood, he only regained intuitive aptitude and telekinesis.
- Niki Sanders injected herself with the Shanti virus when she couldn't fight off Maury Parkman's mind control, resulting in the loss of her enhanced strength (Out of Time).
Abilities shown to be negatively affected by an eclipse are: alchemy, clairsentience, electric manipulation, flight, impenetrable skin, intuitive aptitude, mental manipulation, Mohinder's ability, neurocognitive deficit, poison emission, power absorption, precognition, primal rage, pyrokinesis, rapid cell regeneration, sound manipulation, space-time manipulation, super speed, telekinesis and telepathy.
An evolved human's self-confidence can affect their performance with their ability. An example of this is Hiro's inability to use his new found space-time manipulation power after the death of Charlie. He also believed that he would not be able to use his ability until he had the Kensei's sword in his possession.
- Although Sylar contracted the Shanti virus, resulting in a loss of his abilities, he may have still been able to use his natural ability of intuitive aptitude. He still felt the hunger when he killed Candice (Kindred). He was also able to understand how Maya Herrera's ability worked and help her control it (The Kindness of Strangers).
- For the synthetic formula that gives abilities, see genetic modification formula.
- For the ability that partially restores abilities, see activation and deactivation.