Incense – Herbal Spice

Many of us know incense as a fragrant substance that gives off powerful aromas when burned. In the context of drug abuse, incense traditionally has been used to mask the smell of marijuana so that smokers could avoid detection.

However, recently the term incense has gained a very different definition. There are now herbal incense products that are used as drugs and can be abused.

Herbal incense, sometimes called Spice, can be any number mixed herbs and natural products.

It has been marketed under several different names like:

  • K2
  • Skunk
  • Moon Rocks
  • Spice Gold, etc

The natural product is often spiked with psychoactive substances to make its effect more potent or pronounced.

In March 2011, the Drug Enforcement Agency (DEA) invoked its emergency scheduling authority to outlaw herbal incense that contains any number of synthetic cannabinoids—chemicals with names like JWH-018, JWH-073, and cannabicyclohexanol.

Short Term Effects

In some respects, the short term effects of Spice or herbal incense are quite similar to those of marijuana.

Users experience:

  • Physical relaxation
  • Changes in perception
  • Mild euphoria
  • Reduced motor coordination
  • Decreased information processing.

The effects of herbal incense are generally much more intense than standard marijuana and the negative effects of the synthetic drugs are much more pronounced (less “mellow”).

Short Term Damage

Smoking K2, one of the better studied incense drugs, may produce the following symptoms:

  • Severe agitation
  • Extremely elevated heart rate
  • Elevated blood pressure
  • Coma
  • Suicide attempts
  • Drug dependence.

By comparison, these symptoms and effects rarely occur in people that smoke marijuana or cannabis products.

The American Association of Poison Control Centers received over 2,500 calls about acute “incense” poisoning in 2010.   That is a dramatic increase of from only 50 calls K2 poisoning in 2009.

Long Term Damage

Since Spice or herbal incense is a relatively new drug of abuse, it is hard to know the long term consequences of its use.

However, we do know that some of the chemicals that are used to fortify herbal incense can bind exceptionally tightly to THC receptors in the brain (THC or tetrahydrocannabinol is also the principal intoxicating ingredient in marijuana).

One consequence of this ultra-tight receptor binding is a much higher risk of addiction and dependence. German physicians have reported a case of “incense” withdrawal in a young man who used the drug on a daily basis for eight months.

The withdrawal syndrome was described as causing “inner unrest, drug craving, nocturnal nightmares, profuse sweating, nausea, tremor, and headache.” The young man had extremely high blood pressure and heart rate, as well.

We know that chronic and heavy use cannabis show the following:

  • Mild impairment of cognitive function
  • Decreased attention
  • Decreased learning
  • Decreased memory skills

Some have argued that since the synthetic cannabinoids bind to THC receptors so tightly and strongly that these long term effects are more severe in users of herbal incense.


There have not been any reported deaths caused by a Spice overdose. Nonetheless, numerous emergency department visits have been directly caused by herbal incense intoxication.

Higher amounts of smoked or ingested herbal incense leads to sometimes dangerous effects on the heart and severe anxiety symptoms, similar to panic attacks.

Symptoms and Signs of Abuse

Most commonly used drug tests detect compounds that naturally exist in marijuana itself. The synthetic compounds that are used to doctor Spice/herbal incense do not show up in most urine drug tests.

Users and sellers have exploited this shortcoming to avoid detection, but it also makes it difficult to intervene in cases where a user needs help.

The signs of abuse are similar to those who use marijuana and other cannabis products; however, the effects are more pronounced because the synthetic drug molecules bind THC receptors so tightly.

Adverse Interactions

Incense is not known to interact with other drugs, but since the chemicals in incense bind to the same receptors as cannabis, the effect of using both Spice and marijuana at the same time would be profound and potentially much more dangerous than using either one alone.

People with underlying heart problems could be at particular risk if they use herbal incense because of the dramatic increase in blood pressure and heart rate.

In fact, people with underlying heart disease could theoretically have a heart ischemia (lack of oxygen to the heart) from smoking Spice.



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