Such injuries, including tendon rupture, has been observed up to 6 months after cessation of treatment; higher doses of fluoroquinolones, being elderly, transplant patients, and those with a current or historical corticosteroid use are at elevated risk. The U.S. label for levofloxacin also contains a black box warning for the exacerbation of the symptoms of the neurological disease myasthenia gravis. Similarly, the UK Medicines and Healthcare Products Regulatory Agency recommendations warn of rare but disabling and potentially irreversible adverse effects, and to recommend limiting use of these drugs. Increasing age and corticosteroid use appears to increase the risk of musculoskeletal complications.A wide variety of other uncommon but serious adverse events have been associated with fluoroquinolone use, with varying degrees of evidence supporting causation. These include anaphylaxis, hepatotoxicity, central nervous system effects including seizures and psychiatric effects, prolongation of the QT interval, blood glucose disturbances, and photosensitivity, among others. Levofloxacin may produce fewer of these rare serious adverse effects than other fluoroquinolones.There is some disagreement in the medical literature regarding whether and to what extent levofloxacin and other fluoroquinolones produce serious adverse effects more frequently than other broad spectrum antibacterial drugs.There are some case reports of levofloxacin associated with idiopathic intracranial hypertension.With regard to more usual adverse effects, in pooled results from 7537 patients exposed to levofloxacin in 29 clinical trials, 4.3% discontinued treatment due to adverse drug reactions. The most common adverse reactions leading to discontinuation were gastrointestinal, including nausea, vomiting, and constipation.
: 506–8 : 213

Focal
Focal palmoplantar keratoderma, a type of palmoplantar keratoderma in which large, compact masses of keratin develop at sites of recurrent friction, principally on the feet, although also on the palms and other sites, a pattern of calluses that may be discoid (nummular) or linear. Focal palmoplantar keratoderma with oral mucosal hyperkeratosis (also known as "Focal epidermolytic palmoplantar keratoderma," "Hereditary painful callosities," "Hereditary painful callosity syndrome," "Keratosis follicularis," "Keratosis palmoplantaris nummularis", and "Nummular epidermolytic palmoplantar keratoderma") is an autosomal dominant keratoderma that represents a clinical overlap syndrome with pachyonychia congenita type I but without the classic nail involvement. : 510

Punctate
Punctate palmoplantar keratoderma is a form of palmoplantar keratoderma in which many tiny "raindrop" keratoses involve the palmoplantar surface, skin lesions which may involve the whole of the palmoplantar surface, or may be more restricted in their distribution. : 505 
Type 1: Keratosis punctata palmaris et plantaris (also known as "Autosomal-dominant hereditary punctate keratoderma associated with malignancy," "Buschke–Fischer–Brauer disease," "Davis Colley disease," "Keratoderma disseminatum palmaris et plantaris," "Keratosis papulosa," "Keratoderma punctatum," "Keratodermia punctata," "Keratoma hereditarium dissipatum palmare et plantare," "Palmar and plantar seed dermatoses," "Palmar keratoses," "Papulotranslucent acrokeratoderma," "Punctate keratoderma," "Punctate keratoses of the palms and soles," and "Maculosa disseminata") is a skin condition, an autosomal dominant palmoplantar keratoderma with variable penetrance, characterized clinically by multiple, tiny, punctate keratoses over the entire palmoplantar surfaces, beginning over the lateral edge of the digits. : 509 : 212–213  It has been linked to 15q22-q24.