http://www.lianrokh.ir/docs/mishatxt...onazole_en.PDF
"It can reasonably be concluded that the clinical
efficacy of ketoconazole shampoo in the treatment of
AGA is primarily a function of DHT pathway disruption
rather than an anti-inflammatory effect. In rat studies
ketoconazole caused 5a-R inhibition [28]. Furthermore,
in humans ketoconazole has also been shown to inhibit
the binding of 5a-R to sex hormone globulins [29].
These clinical studies suggest that ketoconazole like
finasteride may in-hibit the production of DHT. Unlike
finasteride ketoconazole has been shown to bind to
human AR [30]. Thus, the effect of ketoconazole on the
DHT pathway may be two-fold: inhibition of DHT
and/or inhibition of DHT binding to AR. Either or both
of these properties would result in reduced incidence of
DHT binding to AR and inhibiting the pathway that
leads to the miniaturizing of hair follicles."

Considering that it blocks DHT production, we can suppose that it would prevent the conversion of nandrolone to the less potent dihydronandrolone (DHN). In other words, it probably works the same way like finasteride. Therefore, I wouldn't recommend taking Nizoral together with nandrolone - although the negative effect would be probably smaller than in finasteride, because Nizoral also blocks binding of androgens to androgen receptors.