A verified bite by Heteroscodra maculata (Togo starburst or ornamental baboon tarantula) resulting in long-lasting muscle cramps

Love Bites – Do Venomous Arachnids Make Safe Pets?

“…and Pterinochilus (44.1%), with the latter two genera also previously being reported for inducing muscle cramps in humans (Ahmed et al, 2009;Fuchs et al, 2018). In some of our cases, those muscle cramps were reported to be long-lasting, sometimes occurring over periods of several weeks or even months.…”

Muscle Spasms – A Common Symptom Following Theraphosid Spider Bites?

“…Thus, these two Old Word genera appear to be the dominant cause for reported muscle cramps attributed to theraphosid spider bites. de Haro and Jouglard, 1998;de Haro and Pommier, 2003;Dinamithra et al, 2013;Fuchs et al, 2018;Fuchs et al, 2014;Hauke and Herzig, 2020;Isbister et al, 2003;Lucas et al, 1994;Raven and Covacevich, 2012;Takaoka et al, 2001 In agreement with previous publications Andreev-Andrievskiy et al, 2017; Herzig and King, 2013), we think the muscle spasms are likely caused by toxins that target voltage-gated ion channels. However, as muscle spasms were recorded from several different, non-closely related Theraphosidae subfamilies ( Figure 1A), any phylogenetic implications appear cryptic, and we cannot rule out that several different venom components (maybe even with additive or synergistic effects) rather than a single toxin are responsible for causing these symptoms.…”

“…Most notably, it was found that muscle cramps caused by Poecilotheria have a delayed onset (on average starting 10 hours after the bite) and are longlasting (7.6 days on average) (Fuchs et al, 2014). A single case of a bite from a "pet" Heteroscodra maculata reported generalized muscle cramps, which started 4 hours and only receded about 2 weeks after bite (Fuchs et al, 2018). All of these previous reports were caused by pet spiders originating from Africa and Asia.…”

“…In the present study, we aimed to analyse the incidence of skeletal muscle spasms in humans as a consequence of theraphosid spider bites and provide zoogeographic and phylogenetic implications (with Theraphosidae phylogeny according to Foley et al, 2019). To this end, we extracted data from published studies (de Haro and Jouglard, 1998; de Haro and Pommier, 2003; Hauke and Herzig, 2020;Isbister et al, 2003;Lucas et al, 1994) and analysed several case reports Dinamithra et al, 2013;Fuchs et al, 2018;Fuchs et al, 2014;Raven and Covacevich, 2012;Takaoka et al, 2001). In addition, we used data from 882 theraphosid venom extractions performed by one of the authors (V.H.)…”

“…Nevertheless, much like the potential lethality of funnel-web spider venom (Herzig et al, 2020), the agonizing effects of theraphosid venoms inducing muscle cramps in humans might have to be considered as an unfortunate evolutionary coincidence. Previous attempts of relieving patients' muscle spasms and easing pain included the administration of benzodiazepines, magnesium and/or calcium, but remained without clear evidence for efficacy Fuchs et al, 2018;Fuchs et al, 2014). Interestingly, in experiments in mice chlorpromazine, an antipsychotic drug, effectively suppressed muscle cramps (Andreev-Andrievskiy et al, 2017).…”