slo⁴ adult display arrhythmic circadian activity pattern are more active throughout the day (and lack any obvious morning peak in activity, while being more active than controls during the evening peak) but no difference in the amount of time spent in sleep per day is observed compared to controls. They also show climbing and flight defects.

Homozygous third instar larvae show a significant increase in bouton size at the neuromuscular junction compared to controls.

Homozygous slo⁴ significantly blocks or reduces tolerance to both benzyl alcohol and ethanol.

Larvae heterozygous for slo⁴ show an increase in bouton formation but do not display significant enhancement in the numbers of type-B and -M satellites or branch segments, compared to controls.

Homozygous mutant animals are healthy and fecund. However, unlike wild-type animals, previous exposure to benzyl alcohol does not induce drug tolerance. Instead mutant flies appear more sensitive - showing a slower recovery from anaesthesia when exposed to benzyl alcohol a second time. slo¹⁸/slo⁴ transheterozygotes are unable to acquire benzyl alcohol resistance, while slo⁴/+ heterozygotes acquire resistance normally.

The majority of slo⁴ flies are arrhythmic both in LD and DD. This phenotype is milder in slo⁴/slo¹ transheterozygotes. Comparison of average activity plots between slo⁴ and wild-type flies shows that in slo⁴ flies there is impaired anticipation of the light transitions around dusk and dawn.

Homozygous slo⁴ indirect flight muscles have broad and abnormally shaped action potentials. Homozygotes are impaired in their flying ability.

Indirect flight muscle action potentials evoked by stimulation of the giant fiber pathway are abnormal during repetitive stimulation in homozygous animals. Typically, the first few action potentials are of normal breadth and shape, but subsequent spikes are abnormally broad and abnormally shaped.

Approximately 90% of homozygotes have a "sticky-feet" phenotype when exposed to a 40[o]C heat pulse: when placed on a flat surface they behave as if their feet are stuck to it when pushed.

slo¹⁸/slo⁴ flies show a 'sticky-feet' phenotype; their feet appear to be stuck to the ground. These flies fly well.

Reduced transmitter release is observed with low external calcium levels when in a normal genetic background or in double mutant combination with Sh¹⁴ or a eag mutant. The EJC amplitude is altered with a high external calcium level. Mutation partially suppresses the synaptic transmission defects conferred by Sh¹⁴, eag mutant or application of 4-AP (eliminates the repetitive firing of motor axons).

Completely eliminates the current conducted by the slo channel.

Homozygotes show increased sensitivity to halothane, chloroform and trichloroethylene in an inebriometer assay (an assay of geotactic and postural behaviour) compared to wild-type flies.

Selective and complete elimination of fast Ca²⁺ activated K⁺ current.