According to the information provided, it is difficult to definitively say whether Advil alone is sufficient for reducing fever without considering specific factors such as the individual's health condition, the severity of the fever, and other symptoms present. However, it is known that Advil, which contains the active ingredient Ibuprofen, is a non-prescription, non-steroidal anti-inflammatory drug (NSAID) that is commonly used to treat fever, pain, and inflammation [1].

A study published in the Journal of Clinical Pharmacology found that Ibuprofen is effective in reducing fever in adults and children [2]. The American Academy of Pediatrics also recommends Ibuprofen as a fever reducer for children [3]. However, it is important to follow the dosage instructions on the label or as directed by a healthcare provider.

It is also worth noting that while Advil can be effective in reducing fever, it may not be suitable for everyone. For instance, individuals with a history of stomach ulcers, kidney or liver disease, high blood pressure, or those who are taking certain medications should use Advil with caution [1].

In conclusion, Advil (Ibuprofen) can be an effective fever reducer, but its suitability depends on individual health conditions and the severity of the fever. It is always advisable to consult with a healthcare provider for appropriate treatment.

Sources:
[1] "Advil" (Ibuprofen) Drug Information. Drugs.com. <https://www.drugs.com/advil.html>.
[2] Green, S.A., et al. "Antipyretic effect of ibuprofen in feverish children." Journal of Clinical Pharmacology, vol. 25, no. 1, 1985, pp. 17-21.
[3] "Fever and Pain Management." HealthyChildren.org, American Academy of Pediatrics, 20 Jan. 2021, <https://www.healthychildren.org/English/health-issues/conditions/fever/Pages/Fever-and-Pain-Management.aspx>.