Severity of Spice addictiveness

Question

We know that Melange is addictive and it's not a mere psychological addiction like in the case of Nicotine; where if you don't smoke it you feel nervous and generally unwell but you won't get seriously sick if going "cold turkey", but it permanently changes your physiology, which means that withdrawal could kill you.

But how long does one have to be exposed to Spice to get addicted to the point of no return? One spiced cake? Few months of regular eating that also turns your eyes blue? And following that, is there a way to break the substance dependency?

The linked question explains the addictive dose but not how often and for how long one would have to use it to create the dependency. For example I could smoke two packets of cigarettes in one day and only get sick, not addicted; smoking few every day (from the same packages) in a period of few weeks would be a serious risk of addiction.

Answer 1

According to "The Road to Dune" in which we find an alternate (and highly abridged) version of Dune, with different characters but a very similar setting, the strong implication seems to be that addiction is almost immediate, especially when encountering a higher quality source for the first time.

Jesse absorbed the startling comments. He tasted the pleasant burning of spice in his mouth and lungs from the saturation underground, from the cups of spice coffee he'd just finished, from the pure sample he'd tasted. Deep inside himself, he already felt an undeniable twinge of longing, not yet a craving but an insistent whisper that suggested how sweet melange would taste right now. Yes, he could envision it becoming an all-consuming personal need.

As to whether it's possible to break the spice addiction, the answer seems to be a firm "no" unless one is relatively young to begin with and not regularly taking higher dosages.

Despite warnings to keep awareness of addiction low key, it was never more than an eyeblink away from Odrade and she felt the accumulated resentments. Mental preparations as an acolyte (firmly impressed in the Agony) had been eroded by Other Memory and accumulations of time. The admonition: “Withdrawal removes an essential of your life and, if it occurs in late middle age, can kill you.” How little that meant now.

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