Onycholysis (drug-induced). This word means separation (-lysis) of nails (onycho-) from nail beds. There are many causes for such a development. The commonest are mechanical. Nails worn long are frequently lifted by being snagged. Excessive soaping and soaking in heavy housework promote separation. The illustration here is of another cause, namely, an idiopathic response by photosensitivity in a patient who had been taking demethylchlortetracycline. Doxycycline also does this.