Minocycline is the most commonly used systemic antibiotic in the long-term treatment (weeks to months) of severe acne vulgaris. Currently much attention is being paid in the Dutch and international literature to the safety of minocycline, after several reports on serious adverse events. The clinical efficacy of minocycline in the treatment of acne vulgaris is better than that of tetracycline and equal to that of doxycycline. The serious adverse events of minocycline therapy described consist of hyperpigmentation of various tissues, autoimmune disorders (systemic lupus erythematosus, autoimmune hepatitis) and serious hypersensitivity reactions (hypersensitivity syndrome reaction, pneumonitis and eosinophilia, and serum sickness-like syndrome). In relation to the number of prescriptions, the number of serious adverse events of minocycline described is small. However, it is very important that prescribing doctors should be aware of the possibility of these adverse events occurring during long-term minocycline therapy and able to recognize the characteristic symptoms at an early stage.