Toxicological Studies with the Hypotensive Agent Minoxidil

The document reports on toxicological studies conducted on the hypotensive agent minoxidil. The drug was given to mice, rats, rabbits, miniature pigs, rhesus monkeys, and dogs for evaluation. The study found that minoxidil was relatively nontoxic to these animals when given at dosages far in excess of those required for hypotensive activity and was not teratogenic in rats and rabbits. However, doses great enough to produce clinical signs of systemic toxicity apparently did so by profoundly altering electrolyte balances. The study also found that a consistent finding in dogs, but in none of the other species studied, was a specific lesion in the wall of the right atrium.