Charlie Sheen's public meltdown/media blitz continues, with riveting interviews aired Monday on morning shows on NBC and ABC, a volatile, rambling conversation streamed on TMZ.com, then a more restrained appearance on CNN's Piers Morgan Tonight.

Yesterday saw: Sheen threaten legal action against his employers, Warner Bros. (which, like TIME, is a unit of Time Warner) and CBS, which last Friday canceled production of Sheen's sitcom Two and a Half Men; his longtime manager, Stan Rosenfield, resign; and the embattled actor drop gems like, "Sorry my life is so much more bitchin' than yours. I planned it that way" and "I am on a drug. It's called Charlie Sheen. It's not available because if you try it once you will die. Your face will melt off and your children will weep over your exploded body."

His recent ranting behavior has led viewers to question whether the actor was still on drugs and denying addiction. Or whether he was exhibiting manic symptoms of bipolar disorder. Or some combination of the two. Sheen's negative drug test suggests that addiction is unlikely to be his only problem.

Although it isn't possible to diagnose patients at a distance, Sheen's case illustrates why it can be sometimes difficult for experts to distinguish between symptoms of a cocaine or meth high, drug withdrawal and bipolar mania. Following is a breakdown of the key characteristics Sheen has recently displayed, and what they may mean.

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Denial. Most people think of addiction when they hear the word "denial," but the truth is that denial is not always seen in addiction. What's more, it's a common phase of reaction to many life experiences, including physical and psychiatric illness. For example, many people's response to hearing a diagnosis of cancer or to learning of the death of a loved one would be to say, "No, I can't believe it. That can't be true."

In addiction and mental illness, denial most commonly appears when the patient is confronted. The same addict who admits to shooting drugs when willingly at a needle exchange will often deny using to someone who's trying to get him into rehab. In the case of a person with a mental disorder like, say, bipolar disorder, he or she will often admit to having symptoms like racing thoughts when it's not being framed as evidence of a mental illness — or, as Sheen put it on TMZ.com, "I don't have burnout of my gearbox. I just go."

However, when confronted by ABC's Andrea Canning about being bipolar, he dismissed the suggestion, saying, "I'm bi-winning ... If I'm bipolar, aren't there moments where a guy, like, crashes and is lying in the corner, like, 'Oh, my God, it's all my mom's fault?' Shut up."

This is why a skillful counselor facing a patient like Sheen won't try to "confront denial." Instead, he or she will "roll with resistance," and work to discuss any life problems that the patient agrees may be problematic. If someone with addiction or bipolar disorder believes that a professional is genuinely trying to help — not attempting to control him or force him to conform to society's demands — denial tends to slip away.

Some might argue that Sheen's resistance to — or even hatred of — 12-step recovery programs and inpatient treatment could be construed as addictive denial. But one size doesn't fit all in the treatment of any disorder, and for some patients, being forced into the 12-step approach can be counterproductive. Simply wanting treatment choice is not a sign of a disease.

"Everyone's approaching him as though he's on drugs," says Dr. Alex DeLuca, a former chief of the Smithers Addiction Research and Treatment Center, regarding Sheen. "It isn't the first thing that would come to my mind, especially when he's exhibiting symptoms off the substances. You can't blame the drug if he doesn't have it in him."

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Grandiosity and narcissism. Sheen has expressed his sense of superiority in many interviews over the last few weeks, telling the Alex Jones radio show, for example: "Newsflash, I am special and I will never be one of you."

In the ABC interview Monday, Sheen responded to a question about being perceived as "erratic," by saying, "You borrow my brain for five seconds and just be, like, Dude, can't handle it, unplug this bastard because, yeah, it fires in a way that is maybe not from this particular terrestrial realm." He said: "I'm tired of pretending like I'm not special."

Many people think grandiosity is a sign of drug abuse, but experts say it may be more likely to signal mania. "Whether someone views his behavior as grandiose would be a matter of personal opinion, but certainly there are lots of people who are grandiose who do not have any addictions and a lot of people with addiction who are not at all grandiose," says A. Thomas Horvath, author of Sex, Drugs, Gambling & Chocolate: A Workbook for Overcoming Addictions and president of the Practical Recovery addiction treatment service in California. "The distinction between high energy and bright mood and a manic episode can be tricky particularly if someone's right in the border region."

Like grandiosity, the narcissistic traits that have clearly been exhibited by Sheen over the last few weeks — for example, in allowing his behavior to result in job loss for dozens of people who make a living on his multimillion dollar show — are neither specific to addiction nor necessary for it. "There's no single addictive personality," says Horvath. "Some traits like impulsivity and grandiosity or depression or anxiety are found in a subset of [addicted people]. But the idea that you could identify a particular personality type and say this person will develop addiction: there's no evidence to support that.

Anger and irritability. When ABC's Canning confronted Sheen about his apparent anger toward his former bosses, he was quick to reframe it as "passion." Irritability can be a symptom of mania and anger appears in addicts, but similar to characteristics like narcissism, grandiosity and denial, they are not specific to nor necessary for either addiction or mania.

"In a manic episode, the mood can be elevated or expansive or irritable," says Horvath. "When someone is highly irritable, that could be considered one way of being manic." But both Horvath and DeLuca note that Sheen's situation could legitimately make anyone irritable. "An average person being treated that way might well be in some manner upset," says Horvath, suggesting that context matters when considering irritability as part of a diagnosis.

Pressured speech. People who are either high on stimulants or experiencing a manic episode may exhibit a phenomenon known as pressured speech in which words seem to flow much faster and with less inhibition than would be normal. Again, consider Sheen's response to the question about being angry: "You borrow my brain for five seconds and just be, like, Dude, can't handle it, unplug this bastard because, yeah, it fires in a way that is maybe not from this particular terrestrial realm."

Likewise, his full response to being asked directly about bipolar disorder seemed to escape his lips with little mental censorship: "What does that mean? Wow. And then what? What's the cure? Medicine? Make me like them? Not gonna happen. I'm bi-winning. I win here and I win there. Now what? If I'm bipolar, aren't there moments where a guy, like, crashes and is lying in the corner, like, 'Oh, my God, it's all my mom's fault?' Shut up. Shut up. Stop, move forward."

But is this bipolar, addiction or both disorders? The determination may be complicated by one final factor: withdrawal.

Withdrawal. During the first few days of abstinence — or sometimes the first weeks or months, depending on the substance and the length of the addiction — many people suffer extreme mood swings. That makes a firm psychiatric diagnosis nearly impossible in patients who have only recently quit drugs.

"You try to detox them so you see what's what," says DeLuca. "Depending on what you know about their history, you may have a good guess. If you don't know this person and don't know their history, clearing the decks [through drug abstinence] is not a bad idea. Over the course of detox, you can get a better psychiatric evaluation."

DeLuca notes, however, that not all medication is off-limits during detox; prescription drugs may be necessary to help keep people comfortable enough to stay in treatment. But until someone has been free from illegal drugs for at least a few weeks, it may not be clear whether their erratic behavior indicates withdrawal or a serious psychiatric problem.

In many cases, it may be both. According to a 2010 paper published in the New York Academy of Sciences, bipolar disorder is more likely than any other psychiatric disorder to be accompanied by substance misuse problems. About 61% of people with bipolar I — the classic form of the disorder in which patients swing from manic highs to depressive lows — also have an addiction. In people with milder bipolar II, the rate of addiction is 48%. In general, at least half of people who suffer from addiction also have a co-existing psychiatric disorder.

Whatever Sheen's particular problems are, a diagnosis is impossible without further evaluation and monitoring. Like any patient, Sheen needs to be evaluated "by a professional who can assess all aspects of mental health, not just the addiction," says Horvath. "If they have their addiction spectacles on that's all they can see, but human beings are complex and rarely have just one problem."

"I hope Mr. Sheen finds someone skilled he can trust and work with," says DeLuca.