Drug interactions
Chlorthalidone + Porfimer
Severity: Moderate
Chlorthalidone and Porfimer: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Porfimer is a photosensitizer used in photodynamic therapy, and chlorthalidone, like other thiazides, can itself cause photosensitivity. Using both may increase the risk or severity of skin reactions to light exposure after porfimer treatment.
What this interaction means in plain words
Chlorthalidone and Porfimer can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Chlorthalidone belongs to Cardiovascular; Porfimer belongs to Miscellaneous.
Why it happens
Additive phototoxic effects of two photosensitizing drugs.
What to do
Reinforce strict light protection for the period specified in the porfimer labeling, including sunscreen and protective clothing. Consider whether chlorthalidone can be temporarily replaced by a non-photosensitizing antihypertensive.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Chlorthalidone
Other interactions of Porfimer
Frequently asked questions
Can I take Chlorthalidone with Porfimer?
MediHelp rates the interaction as moderate. Chlorthalidone and Porfimer can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Porfimer is a photosensitizer used in photodynamic therapy, and chlorthalidone, like other thiazides, can itself cause photosensitivity. Using both may increase the risk or severity of skin reactions to light exposure after porfimer treatment.
How serious is the interaction between Chlorthalidone and Porfimer?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Reinforce strict light protection for the period specified in the porfimer labeling, including sunscreen and protective clothing. Consider whether chlorthalidone can be temporarily replaced by a non-photosensitizing antihypertensive.
What other medicines interact with Chlorthalidone?
MediHelp also lists interactions of Chlorthalidone with, for example, Amifostine, Atenolol-chlorthalidone, Candesartan-hydrochlorothiazide. The full list is on the Chlorthalidone page.
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