Powders & Potions. Wood alcohol (methanol) can contaminate moonshine whiskey and lead to rapid, permanent vision loss. Tobacco-alcohol amblyopia is a vitamin deficiency that may be partially reversible. Talc powder, as a contaminant of intravenous drugs, can cause capillary occlusion in the retina. Marijuana and hallucinogens alter the visual experience, but do not cause vision loss. Mj is good for glaucoma.
Injectable. Impure injectable drugs can block arteries in the retina and cause blindness. Heroin and methamphetamines can be mixed with talc and starches that can cause this.
Not directly. Drugs of abuse in their pure form cannot disturb the vision except for the psychedelic effects causing visual hallucinations. You can lose vision by 1) overdose with loss of consciousness leading to stroke in the eye or visual part of the brain 2) adulterated drugs containing dangerous substances 3) injection of contaminated drugs. Best solution? Get off illegal substances.