Baudelaire next worked on a translation and adaptation of Thomas De Quincey's Confessions of an English Opium Eater. Other works in the years that followed included Petits Poèmes en prose (Small Prose poems); a series of art reviews published in the Pays, Exposition universelle (Country, World Fair); studies on Gustave Flaubert (in L'Artiste, October 18, 1857); on Théophile Gautier (Revue contemporaine, September 1858); various articles contributed to Eugene Crepet's Poètes francais; Les Paradis artificiels: opium et haschisch (French poets; Artificial Paradises: opium and hashish) (1860); and Un Dernier Chapitre de l'histoire des oeuvres de Balzac (A Final Chapter of the history of works of Balzac) (1880), originally an article "Comment on paye ses dettes quand on a du génie" ("How one pays one's debts when one has genius"), in which his criticism turns against his friends Honoré de Balzac, Théophile Gautier, and Gérard de Nerval.
By 1859, his illnesses, his long-term use of laudanum, his life of stress, and his poverty had taken a toll and Baudelaire had aged noticeably. But at last, his mother relented and agreed to let him live with her for a while at Honfleur. Baudelaire was productive and at peace in the seaside town, his poem Le Voyage being one example of his efforts during that time. In 1860, he became an ardent supporter of Richard Wagner.
His financial difficulties increased again, however, particularly after his publisher Poulet Malassis went bankrupt in 1861. In 1864, he left Paris for Belgium, partly in the hope of selling the rights to his works and also to give lectures. His long-standing relationship with Jeanne Duval continued on-and-off, and he helped her to the end of his life. Baudelaire's relationships with actress Marie Daubrun and with courtesan Apollonie Sabatier, though the source of much inspiration, never produced any lasting satisfaction. He smoked opium, and in Brussels he began to drink to excess. Baudelaire suffered a massive stroke in 1866 and paralysis followed. After more than a year of aphasia, he received the last rites of the Catholic Church. The last two years of his life were spent, in a semi-paralyzed state, in "maisons de santé" in Brussels and in Paris, where he died on 31 August 1867. Baudelaire is buried in the Cimetière du Montparnasse, Paris.
Many of Baudelaire's works were published posthumously. After his death, his mother paid off his substantial debts, and at last she found some comfort in Baudelaire's emerging fame. "I see that my son, for all his faults, has his place in literature." She lived another four years.