Guanoxan is a sympatholytic drug that was marketed as Envacar by Pfizer in the UK to treat

high blood pressure Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high bl ...

. It was not widely used and was eventually withdrawn from the market due to liver toxicity.

References

Adrenergic release inhibitors Benzodioxans Guanidines Hepatotoxins Withdrawn drugs {{antihypertensive-stub