My turn

Cassie dropped her pants for me in Brisbane. Brock ran a personal best over 10 km for me in Ottawa. Susan abstained from alcohol for a month for me in Beijing. Kim cycled 55 km for me in Sydney.

I think it's my turn

The City2Sea is a 14 km run in Melbourne and takes place mid-November.

I'm going to be raising money for The Warwick Foundation - the first and largest Australian organisation supporting 18 to 40 year olds with cancer.

The race will take place after three days of Cycle 5 of my chemotherapy. This is good because it means I will be high on hormones, but bad because I will probably be tired as hell.

I'll be running with my PICC line and bum bag (of the medical apparatus kind) and so won't be going for a PB; it's the thought and effort that counts after all.

You can sponsor me here.

No pressure

I only have Stage 3 cancer AND will be running 14 km for CHARITY in the middle of CHEMOTHERAPY, 14 weeks AFTER surgery that removed 15% of my body weight and sent my resting heart rate UP 30 beats per minute.

Roid rage

Cancer has given me tattoos and a scar that looks like I lost an encounter with a Samurai, or maybe a shark, or maybe a samurai-wielding shark. Macho factors for sure.

But the only way to really become an Ultimate Macho Man is to work at it from the inside, and that means 'roids.

By NinjaMouf (devianart.com)

Even the name of the steroid I take sounds tough.

Dex: 100% MAN made

Dexamethasone is a synthetic steroid designed to mimic a steroid our bodies make called cortisol. Cortisol is a steroid released by the adrenal glands perched on top of the kidneys. Cortisol is helpful during stressful situations (like a battle with a samurai-wielding shark) because it contributes to our 'flight or fight' response.

Cortisol and Dex are glucocorticoids, which means they basically affect the way glucose is used by the cells in your body. During times of immediate stress (shark with sword) your body needs quick access to plenty of energy and cortisol makes this happen. Cortisol also minimises our perception of pain, boosts the immune system and acts as an anti-inflammatory agent.

Cortisol x 80 = Dex

Chemists didn't muck around when they made Dex because it is up to 80 times more powerful than cortisol. Dex also sticks around in the body longer than cortisol: its half life (the amount of time it takes to lose half of its ability to affect the body) is up to 54 hours (it's 8 hours for cortisol).

Dex is commonly used in cancer treatments to control nausea, but no one is really sure how it works. One of the fun things about having cancer is coming across treatments that work but no one knows why (there are several examples of this).

Unlike other anti-nausea drugs that directly block serotonin receptors and the main road leading to the Vomit Centre, Dex works another way; they're just not sure how, or why, or where.

Some things are known though: side effects

The list is long, but here are the most interesting ones:

• Increased appetite and weight gain (note: not muscle gain)
• Convulsions
• Insomnia
• Anxiety
• Personality changes, depression
• Irritability, euphoria, mania

I now put on up to 1 kg a week of body mass, I'm writing this article at 3:40 am, I got anxious today about something small, I breakout in a sprint when cycling for no reason except that I can, and when my thoughts start racing, they're matched only by my racing heartbeat.

But I haven't vomited once.

Chemo = Vom

Looking at or smelling chemotherapy drugs don't make you feel sick; they have to be inside the body to cause nausea and vomiting. And this doesn't involve the stomach (well, not at first, the vomiting bit is all stomach), it involves the small intestine.

Because cells lining the small intestine are particularly sensitive to chemotherapy drugs.

When these cells are damaged by chemotherapy drugs, they release the neurotransmitter serotonin. The name serotonin is loaded with meanings related to happiness in people and bullying in male animals, but around 90% of serotonin in the human body is found in cells lining the gut, where it has the mundane job of regulating how fast the digestive system pushes food along.

Three roads lead to vomit town.

The main road

Serotonin released by intestinal cells damaged by chemotherapy drugs is detected by vagal nerves hanging out near these cells. Vagal nerves send information (WARNING: Gut has been poisoned) to the medulla oblogata, the region of the brain where the Vomiting Centre is located. Then you feel sick and vomit.

The small side road

Serotonin released by upset intestinal cells enters the blood stream, chemoreceptor trigger zones detect it and alert the Vomiting Centre that something isn't right (WARNING: High levels of serotonin in blood stream mean gut is poisoned). Then you feel sick and vomit.

The smaller side road

The chemo itself is directly detected by the chemoreceptor trigger zones that alert the Vomiting Centre (WARNING: Poison in blood stream). Then you feel sick and vomit.

Controlling the flow

Oxaliplatin is a non-targeted chemotherapy drug and a part of my treatment. It is especially emetic, meaning it causes nausea and vomiting (emesis) in nearly everyone that has it. It even causes nausea and vomiting when given to patients in combination with super duper drugs that stop nausea and vomiting.

Drugs that try and stop nausea and vomiting act as road blocks along the streets that lead to vomit town. I'm a particular fan of one of these drugs, a steroid, because I now put on one kilogram of weight a week, have bouts of anxiety, and suffer from insomnia.

I refer to these side effects collectively as Roid Rage.

Vomiting Centre

Vomit Centre is perhaps the coolest name of any part of the human body.

It is located in the stem of your brain, in an area called the medulla oblongata. The medulla oblongata is old, meaning it is also found in the brains of other critters not so closely related to humans, such as fish. Old parts of the brain tend to do the really important stuff that animals with brains have been doing for millions of years, such as breathing and maintaining a beating heart.

The Vomiting Centre collects information from across the body and when this part of the brain becomes excited (in the neurological sense, not the 'I can't wait for the next episode of True Blood' sense) people vomit.

Signals INTO the Vomiting Centre

From other parts of the brain: You know these parts are talking to the Vomiting Centre when you want to vomit because you see someone else vomit. Or when my Nanna smells really ripe bananas and her stomach tries to empty itself.

From organs: You know organs are talking to the Vomiting Centre when you eat so much that your stomach expands and you throw up. Or when you have an intestinal blockage and you vomit.

From the inner ear: You know when your balance system is talking to the Vomiting Centre when you get get off a roller coaster feeling very dizzy, and vom.

From chemoreceptor trigger zones: These trigger zones are also in the medulla oblongata. They detect chemical abnormalities and poisons throughout the body, meaning it's chuck time.

Signals OUT OF the Vomiting Centre

Regardless of how the Vomiting Centre becomes excited (spending too long on a roller coaster, blocked intestine, being vomited on) the final action is the same: vomition.

Why does chemo = nausea and vomiting?

The way chemotherapy drugs make the body vomit isn't as straight forward as you might think. The next blog post will explain why chemotherapy makes the body vomit.

And it doesn't involve the stomach (well, not at first, as we all know the act of vomiting is ALL stomach).

Higher human

Yeah I know, very clever.

I'm slowly morphing into a higher human. Something half man, half medical apparatus.

This is the latest addition to my collection. It's a clever piece of latex designed to protect a PICC line from the evils of water.

It will replace something I now use and which I call The Plastic Bag With Rubber Bands.

Does my bicep look big in this?