Question

Does Prozac interact with PIs and could this cause hair loss?

3 November 2007. Related: All topics, Drug interactions, Side effects.

I am a 39years old female – on a healthy diet and a healthy weight. I have been taking ritonavir 100mg, Invirase (saquinavir) and Truvida (tenofovir+FTC) for 2 months.

I also take fluoxetine 20mg (Prozac) and Cilest (a combined oral contraceptive that contains two active ingredients, ethinylestradiol and norgestimate) as my pituitary gland has stopped producing estrogen.

Since starting antivirals I have had rashes and hair loss – these are uncommon on my combination I am told. I take the antihistimine cetrizine hydrocloride 10mg for the rash and hydrocortisol+antifungal cream for the rash.

The rash is manageable and seems to have improved. The hair loss is slowly reaching a stage where I cannot live with it. Could I be an interaction with the fluoxetine? Should I switch to another combination or stop the fluoxetine or do something else?

Please help.

Answer

Answer: Simon Collins

First, you need to go back to your doctor to talk about all of this.

The hair loss has rarely been reported with some HIV drugs. Although the reports are difficult to find, 3TC has been linked to hair loss, so potentially FTC may be causing this.

But it seems more likely that this could be related to the fluoxetine (Prozac) which does list hair loss as a potential side effect in the full prescribing information (PDF).

This risk may have been prompted by an interaction as ritonavir can increase levels of Prozac. Eihter switching to an alternative antidepressant or premenstual drug (which ever indication the Prozac is prescribed for), or using a lower dose of Prozac (in consultation with your doctor), may both help. Withdrawl effects can occur if you just stop Prozac – which is why you need to talk to your doctor first. Rash is also listed as a side effect of Prozac.

Protease inhibitors can also potentially interact with oral contraceptives (recommendations are to use with other contraceptives). This is a specialist area and your doctor should discuss your whole combination with a specialist HIV pharmacist.