Other serotonergic pharmacologics in question
The SSRI antidepressants raise blood serotonin levels, and thus may be capable of the same risks, though it is thought that the risk is substantially lower with such drugs. The amino acid L-tryptophan also raises blood serotonin, and may present the same risk as well; though, again, the risk is considered to be low.However, the tryptophan derivative 5-HTP (5-hydroxytryptophan), used in the treatment of depression, raises blood serotonin level considerably. It has yet to be reported to be associated with valve disease or other fibrosis, but for the previous theoretical reasons, it has been suggested as a possible danger.When 5-HTP is used in medicine, it is generally administered along with carbidopa, which prevents the peripheral decarboxylation of 5-HTP to serotonin and so ensures that only brain serotonin levels are increased without producing peripheral side effects, however 5-HTP is also sold without carbidopa as a dietary supplement, and may have increased risks when taken by itself without carbidopa. In non-human great apes
Cardiac fibrosis is common in non-human great apes in human care. The term idiopathic myocardial fibrosis was coined to emphasize this disease is likely different from the above described forms of cardiac fibrosis in humans. The etiology is not known, though vitamin D deficiency is a potential suspected cause at least in chimpanzees. Possible treatments
The most obvious treatment for cardiac valve fibrosis or fibrosis in other locations, consists of stopping the stimulatory drug or production of serotonin.
Rocuronium bromide (brand names Zemuron, Esmeron) is an aminosteroid non-depolarizing  neuromuscular blocker or muscle relaxant used in modern anaesthesia to facilitate tracheal intubation by providing skeletal muscle relaxation, most commonly required for surgery or mechanical ventilation. It is used for standard endotracheal intubation, as well as for rapid sequence induction (RSI). Pharmacology
Mechanism of action
Rocuronium bromide is a competitive antagonist for the Nicotinic acetyl-choline receptors at the neuromuscular junction. Of the Neuromuscular-blocking drugs it is considered to be a non-depolarizing neuromuscular junction blocker, because it acts by dampening the receptor action causing muscle relaxation, instead of continual depolarisation which is the mechanism of action of the depolarizing neuromuscular junction blockers, like succinylcholine. It was designed to be a weaker antagonist at the neuromuscular junction than pancuronium; hence its monoquaternary structure and its having an allyl group and a pyrrolidine group attached to the D ring quaternary nitrogen atom. Rocuronium has a rapid onset and intermediate duration of action.There is considered to be a risk of allergic reaction to the drug in some patients (particularly those with asthma), but a similar incidence of allergic reactions has been observed by using other members of the same drug class (non-depolarizing neuromuscular blocking drugs).The γ-cyclodextrin derivative sugammadex (trade name Bridion) has been recently introduced as a novel agent to reverse the action of rocuronium.